Who was the creator for Judaism?

Answer 1

According to The Bible, Abraham was the first monotheist. He traveled from his hometown of Haran to the Land of Canaan (Israel). His great-grandchildren, the sons of Jacob, settled in Egypt due to a famine and their descendants formed the Israelite nation. The Exodus from Egypt led to the giving of the law at Mount Sinai (in the Sinai desert), creating the Jewish religion.

Answer 2

The tradition of the Jewish people, and the Torah Sages and Talmud, is that Abraham founded Judaism. This tradition is implicit in many passages in the prophets (e.g. Isaiah 41:8) and throughout the Talmud (e.g. Yoma 28b) and is borne out by a reading of the book of Genesis.

Answer 3

The Jewish answer would be that Judaism was created by God, not by a person. The historical answer would be that the inventor of Judaism is not known. At some point, the tribes of Israel changed their belief in a polytheistic religion to belief in a monotheistic religion, but exactly whose idea that was, we do not know.

• Answer:

Tradition states that Abraham (18th century BCE) founded Judaism, and Moses later received the Torah from God.
Abraham (18th century BCE), tenth-generation descendant of Noah, of Hebrew lineage, was the son of Terah, uncle of Lot, father of Isaac, grandfather of Jacob, and forefather of the Israelites. His story is in Genesis ch.11 (end), through ch.25. Jewish tradition states that he was the first to actively spread belief in One God; and it is in his merit that Jews continue to exist (Genesis 18:19, and ch.17).

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Abraham came from ancestry that had been aware of God a couple of centuries earlier but had afterwards slipped into idolatry (Joshua 24:2). By the time of Abraham, the area where he lived was full of pagan cults; they were polytheistic, worshiping multiple deities.
Abraham became the first to advance the idea of ethical monotheism: the worship of One God, and the appropriate ethical code of conduct.

• 
  

Nimrod, the idolatrous tyrant, had brought Abraham's father (Terah) from the Semitic ancestral seat near the confluence of the Balikh and the Euphrates, and instated him in a position of power in his army in the royal Babylonian city of Ur, where Abraham was born. Nimrod persecuted any who would question his idolatrous cult.
The Kuzari (Rabbi Judah HaLevi, 1075-1141) states that Abraham was gifted with high intelligence; and, as Maimonides (1135-1204) describes, Abraham didn't blindly accept the ubiquitous idolatry. The whole populace had been duped, but the young Abraham contemplated the matter relentlessly, finally arriving at the conclusion that there is One God and that this should be taught to others as well. This is what is meant by his "calling out in the name of the Lord" (Genesis ch.12). As a young man, he remonstrated with passersby in public, demonstrating to them the falsehood of their idols; and our tradition tells how he was threatened and endangered by Nimrod.
Subsequently, Terah relocated to Harran; and it is here that Abraham began to develop a circle of disciples (Rashi commentary, on Genesis 12:5).
Later, God told Abraham in prophecy to move to the Holy Land, which is where he raised his family.
He continued his contemplations, eventually arriving at the attitudes and forms of behavior which God later incorporated into the Torah given to Moses.
Abraham became the greatest thinker of all time. His originality, perseverance, strength of conviction, and influence, cannot be overestimated.
Abraham, with God's help, trounced the supremacy of the evil Nimrod.
He received God's promise of inheriting the Holy Land (Genesis ch.13).
He strove to raise a family (Genesis ch.15, 17, and 24) which would serve God (Genesis 18:19); and God eventually blessed his efforts, granting him numerous descendants (ibid., ch.16, 21 and 25), in keeping with His promise (Genesis ch.17).
Abraham founded the Jewish people and lived to see his work live on in the persons of Isaac and Jacob; and he taught many other disciples as well (Talmud, Yoma 28b).
He saved the population of the south of Canaan from invading foreign kings (Genesis 14); and he was feared by neighboring kings (ibid., ch.12 and 20).
Abraham gave tithes (Genesis ch.14), entered into a covenant with God (Genesis ch.15 and 17), welcomed guests into his home (Genesis ch.18) unlike the inhospitable Sodomites (Genesis ch.19), prayed for people (Genesis ch.18), rebuked others when necessary (Genesis ch.20), eulogized and buried the deceased (Genesis ch.23), and fulfilled God's will unquestioningly (Genesis ch.22). He became renowned as a prince of God (Genesis 23:6).
The gravesite of Abraham, Isaac and Jacob and their wives (Genesis 49:29-32) is located in Hebron and has been known and attested to for many centuries.
All of the above practices of Abraham were based upon the ways of God, which Abraham understood through his contemplations. These, and similar personality traits, were the teachings of Abraham and his descendants (unlike idolatry, which had no moral character; with worship of the gods accompanied by things such as human sacrifice, "sacred" prostitution, and animal worship).
It is therefore clear why God expresses His love for Abraham (Isaiah 41:8) and calls Himself the God of Abraham (Genesis 26:24), and says that Abraham obeyed Him fully (Genesis 26:5). And this is why Abraham is credited with having begun the religion which became known as Judaism. (However, Abraham and his descendants observed their traditions voluntarily, until the Giving of the Torah to Moses 3325 years ago, when God made it obligatory.)

Answer 4

Judaism was founded in approximately 2000-1500 B.C. in Mesopotamia (modern-day Iraq). Many say that Abraham was the father of the religion, but scholars still debate it today. Some say that Judaism has not one, single founder, but is a religion where beliefs and customs were added over time.

Answer:The tradition of the Jewish people, and their Sages and Talmud, has always been that Abraham founded Judaism. This is implicit in many passages in the prophets (e.g. Isaiah 41:8) and throughout the Talmud (e.g. Yoma 28b) and is clearly borne out by a reading of Genesis, even without commentaries.

God calls himself "the God of Abraham, Isaac and Jacob" no fewer than eighteen times in the Torah, and that is how we address Him every day in the Shemoneh Esrei prayer.

However, Abraham and his descendants observed their traditions voluntarily, until the Giving of the Torah to Moses, when God made it obligatory.

Abraham (18th century BCE) came from ancestry that had been God-fearing a couple of centuries earlier but had slipped into idolatry in recent generations (Joshua 24:2). Nimrod, the idolatrous tyrant, had brought Abraham's father (Terah) from the Semitic ancestral seat near the conjunction of the Balikh and the Euphrates, and instated him in a position of power in his army in the royal Babylonian city of Ur. Nimrod persecuted any who would question his idolatrous cult.

The Kuzari (Rabbi Judah HaLevi, 1075-1141) states that Abraham was gifted with high intelligence; and, as Maimonides (1135-1204) describes, Abraham didn't blindly accept the ubiquitous idolatry. The whole populace had been duped, but the young Abraham contemplated the matter relentlessly, finally arriving at the conclusion that there is One God and that this should be taught to others as well. This is what is meant by his "calling out in the name of the Lord" (Genesis ch.12). As a young man, he remonstrated with passersby in public, demonstrating to them the falsehood of their idols; and our tradition tells how he was threatened and endangered by Nimrod. Later in life, God said to Abraham in prophecy to move to the Holy Land, which is where Abraham raised his family.

He continued his contemplations, eventually arriving at the attitudes and forms of behavior which God later incorporated into the Torah given to Moses. Abraham taught disciples (Talmud, Yoma 28b), gave tithes (Genesis ch.14), strove to raise a family (Genesis ch.15, 17, and 24) which would serve God, made a covenant with God (Genesis ch.15 and 17), welcomed guests into his home (Genesis ch.18) unlike the inhospitable Sodomites (Genesis ch.19), prayed for people (Genesis ch.18), rebuked others when necessary (Genesis ch.20), eulogized and buried the deceased (Genesis ch.23), and fulfilled God's will unquestioningly (Genesis ch.22). He became renowned as a prince of God (Genesis 23:6).

It is therefore clear why God expresses His love for Abraham (Isaiah 41:8) and calls Himself the God of Abraham (Genesis 26:24), and says that Abraham obeyed Him fully (Genesis 26:5). And this is why, according to our tradition, Abraham is credited with having founded the religion which became known as Judaism.

Answer 5

Tradition holds that Judaism began with Abraham in the land of Israel, around the Year 2000 BCE. There is archaealogical evidence for Hebrews (ancient Jews) in the Land of Israel as far back as 3600 BCE. Rabbinic Judaism began after the year 70 CE.

Answer 6

Tradition states that Abraham (18th century BCE) founded Judaism, and Moses later received the Torah from God.See also:

Timeline of Jewish history
Archaeology

Abraham, tenth-generation descendant of Noah, of Hebrew lineage, was the son of Terah, uncle of Lot, father of Isaac, grandfather of Jacob, and ancestor of the Israelites. His story is in Genesis ch.11 (end), through ch.25. Jewish tradition states that he was the first to actively spread belief in One God; and it is in his merit that Jews continue to exist (Genesis 18:19, and ch.17).

Abraham came from ancestry that had been aware of God a couple of centuries earlier but had afterwards slipped into idolatry (Joshua 24:2). (See: How did polytheism start.)

By the time of Abraham, the area where he lived was full of pagan cults; they were polytheistic, worshiping multiple deities. Abraham became the first to advance the idea of ethical monotheism: the worship of One God, and the appropriate ethical code of conduct.

Nimrod, the idolatrous tyrant, had brought Abraham's father (Terah) from the Semitic ancestral seat near the confluence of the Balikh and the Euphrates, and instated him in a position of power in his army in the royal Babylonian city of Ur, where Abraham was born. Nimrod persecuted any who would question his idolatrous cult.

The Kuzari (Rabbi Judah HaLevi, 1075-1141) states that Abraham was gifted with high intelligence; and, as Maimonides (1135-1204) describes, Abraham didn't blindly accept the ubiquitous idolatry. The whole populace had been duped, but the young Abraham contemplated the matter relentlessly, finally arriving at the conclusion that there is One God and that this should be taught to others as well. This is what is meant by his "calling out in the name of the Lord" (Genesis ch.12).

As a young man, he remonstrated with passersby in public, demonstrating to them the falsehood of their idols; and our tradition tells how he was threatened and endangered by Nimrod.
Subsequently, Terah relocated to Harran; and it is here that Abraham began to develop a circle of disciples (Rashi commentary, on Genesis 12:5).

Later, God told Abraham in prophecy to move to the Holy Land, which is where he raised his family.

He continued his contemplations, eventually arriving at the attitudes and forms of behavior which God later incorporated into the Torah given to Moses. (See: Thirteen basic Jewish beliefs)

Abraham became the greatest thinker of all time. His originality, perseverance, strength of conviction, and influence, cannot be overestimated.

Abraham, with God's help, trounced the supremacy of the evil Nimrod.

He received God's promise of inheriting the Holy Land (Genesis ch.13).

He strove to raise a family (Genesis ch.15, 17, and 24) which would serve God (Genesis 18:19); and God eventually blessed his efforts, granting him numerous descendants (ibid., ch.16, 21 and 25), in keeping with His promise (Genesis ch.17).

Abraham founded the Jewish people and lived to see his work live on in the persons of Isaac and Jacob; and he taught many other disciples as well (Talmud, Yoma 28b).

He saved the population of the south of Canaan from invading foreign kings (Genesis 14); and he was feared by neighboring kings (ibid., ch.12 and 20).

Abraham gave tithes (Genesis ch.14), entered into a covenant with God (Genesis ch.15 and 17), welcomed guests into his home (Genesis ch.18) unlike the inhospitable Sodomites (Genesis ch.19), prayed for people (Genesis ch.18), rebuked others when necessary (Genesis ch.20), eulogized and buried the deceased (Genesis ch.23), and fulfilled God's will unquestioningly (Genesis ch.22).

He became renowned as a prince of God (Genesis 23:6).

The gravesite of Abraham, Isaac and Jacob and their wives (Genesis 49:29-32) is located in Hebron and has been known and attested to for many centuries.

All of the above practices of Abraham were based upon the ways of God, which Abraham comprehended through his contemplations. These, and similar personality traits, were the teachings of Abraham and his descendants (unlike idolatry, which had tended to go hand in hand with cruel, licentious and excessive behavior, since the caprices which were narrated concerning the idols were adopted as an excuse to imitate those types of behavior). (See: Cruelties of the polytheists)

It is therefore clear why God expresses His love for Abraham (Isaiah 41:8) and calls Himself the God of Abraham (Genesis 26:24), and says that Abraham obeyed Him fully (Genesis 26:5). And this is why Abraham is credited with having begun the religion which became known as Judaism. (However, Abraham and his descendants observed their traditions voluntarily, until the Giving of the Torah to Moses 3325 years ago, when God made it obligatory.)

Answer 7

According to tradition, Abraham founded Judaism, and Moses later received the Torah from God.(See also: Timeline of Jewish history)

Abraham, tenth-generation descendant of Noah, of Hebrew lineage, was the son of Terah, uncle of Lot, father of Isaac, grandfather of Jacob, and ancestor of the Israelites. His story is in Genesis ch.11 (end), through ch.25. Jewish tradition states that he was the first to teach belief in One God; and it is in his merit that Jews continue to exist (Genesis 18:19, and ch.17).

Abraham (18th century BCE) came from ancestry that had been aware of God a couple of centuries earlier but had afterwards slipped into idolatry (Joshua 24:2). (See: How did polytheism start?)

Nimrod, the idolatrous tyrant, had brought Abraham's father (Terah) from the Semitic ancestral seat near the confluence of the Balikh and the Euphrates, and instated him in a position of power in his army in the royal Babylonian city of Ur, where Abraham was born. Nimrod persecuted any who would question his idolatrous cult.

The Kuzari (Rabbi Judah HaLevi, 1075-1141) states that Abraham was gifted with high intelligence; and, as Maimonides (1135-1204) describes, Abraham didn't blindly accept the ubiquitous idolatry. The whole populace had been duped, but the young Abraham contemplated the matter relentlessly, finally arriving at the conclusion that there is One God and that this should be taught to others as well. This is what is meant by his "calling out in the name of the Lord" (Genesis ch.12).

As a young man, he remonstrated with passersby in public, demonstrating to them the falsehood of their idols; and our tradition tells how he was threatened and endangered by Nimrod.
Subsequently, Terah relocated to Harran; and it is here that Abraham began to develop a circle of disciples (Rashi commentary, on Genesis 12:5).

Later, God told Abraham in prophecy to move to the Holy Land, which is where Abraham raised his family.
He continued his contemplations, eventually arriving at the attitudes and forms of behavior which God later incorporated into the Torah given to Moses. (See: Thirteen basic Jewish beliefs)

Abraham, with God's help, trounced the supremacy of the evil Nimrod.

He received God's promise of inheriting the Holy Land (Genesis ch.13).

He strove to raise a family (Genesis ch.15, 17, and 24) which would serve God (Genesis 18:19); and God eventually blessed his efforts, granting him many children (ibid., ch.16, 21 and 25), as He had promised (Genesis ch.17).

Abraham founded the Jewish people and lived to see his work live on in the persons of Isaac and Jacob; and he taught many other disciples as well (Talmud, Yoma 28b).

He saved the population of the south of Canaan from invading foreign kings (Genesis 14); and he was feared by neighboring kings (ibid., ch.12 and 20).

Abraham gave tithes (Genesis ch.14), entered into a covenant with God (Genesis ch.15 and 17), welcomed guests into his home (Genesis ch.18) unlike the inhospitable Sodomites (Genesis ch.19), prayed for people (Genesis ch.18), rebuked others when necessary (Genesis ch.20), eulogized and buried the deceased (Genesis ch.23), and fulfilled God's will unquestioningly (Genesis ch.22).

He became renowned as a prince of God (Genesis 23:6).

The gravesite of Abraham, Isaac and Jacob and their wives (Genesis 49:29-32) is located in Hebron and has been known and attested to for many centuries.

All of the above practices of Abraham were based upon the ways of God, which Abraham comprehended through his contemplations. These, and similar personality traits, were the teachings of Abraham and his descendants (unlike idolatry, which had tended to go hand in hand with cruel, licentious and excessive behavior, since the caprices which were narrated concerning the idols were adopted as an excuse to imitate those types of behavior). (See: Cruelties of the polytheists)

It is therefore clear why God expresses His love for Abraham (Isaiah 41:8) and calls Himself the God of Abraham (Genesis 26:24), and says that Abraham obeyed Him fully (Genesis 26:5). And this is why Abraham is credited with having begun the religion which became known as Judaism. (However, Abraham and his descendants observed their traditions voluntarily, until the Giving of the Torah to Moses 3325 years ago, when God made it obligatory.)

Moses was an Israelite, a great-great grandson of Jacob. He was born 245 years after the death of Abraham. The time when Moses was born was when the Pharaoh had ordered his people to kill all Israelite male infants because he (Pharaoh) was afraid that the Israelites would become too strong for him (Exodus ch.1-2).

Moses' mother didn't want him to die. So she made a basket for him and put him in it to float in the Nile reeds. He was found by Pharaoh's daughter, who took pity on him (Exodus ch.2) and raised him as her own son. (See: How did Moses know he was an Israelite?)

Moses was forced to flee after killing a cruel Egyptian taskmaster, and went to Midian, where he wedded the daughter of Jethro.

He eventually achieved the highest level of prophecy (Deuteronomy ch.34) and was called upon by God (Exodus ch.3). He brought the Israelites out of Egyptian slavery (Exodus ch.12). He received the Torah from God (Exodus 24:12) and later recorded it in writing (Deuteronomy 31:24). He went up on Mount Sinai for 40 days and nights (Deuteronomy ch.9-10) and brought down the Two Stone Tablets with the Ten Commandments (Exodus 31:18). He brought the Israelites into the covenant with God (Exodus ch.19 and ch.24), and he oversaw the building of the Tabernacle (Exodus ch.35-40). He was the humblest of men and the greatest of prophets (Numbers ch.12).

See also:

What problems did Moses face and overcome?

Answer 8

Tradition states that Judaism began with Abraham, some 3800 years ago when he rejected the universal idolatry of his time and concluded that there is only one God.

Historically, the creation, or evolution, of Judaism is very different. Archaeologists, historians and scholars have pieced together a good deal of information about the early history of the Israelites and the evolution of their religion. They say that the Hebrew people did not emerge out of Egypt as stated in the Bible, but that they were themselves Canaanites who migrated internally from the region of the rich coastal cities to settle in the hitherto sparsely populated hinterland.

Like all Canaanites and other north-western Semitic peoples, the Hebrews worshipped several gods and goddesses known throughout the region, including Baal and El (biblical: Elohim). A later addition to the Israelite pantheon was a new God from the south (Midian), Yahweh (biblical Hebrew: YHWH). Gradually, Yahweh and El began to be seen as the same God, and the attributes of Baal were also absorbed into Yahweh.

Israel was still polytheistic at the time of its destruction in 722 BCE, but Judasim continued to evolve, becoming monolatrous and aniconic (no longer using idols or images). By the time of the Return from the Babylonian Exile and the building of the second Temple in Jerusalem, the Jews were strongly monotheistic and much of the Old Testament had been compiled.

Rabbinic Judasim was effectively created by the destruction of the Temple in 70 CE. No longer were the Pharisees and Sadducees to be the religious leaders of the Jews, and no longer could animal sacrifices be made in the Temple. New writings brought Jewish understanding of the Tanach, or Hebrew Bible, up to date.

Answer 9

The tradition of the Jewish people, and the Torah Sages and Talmud, is that Abraham (18th century BCE) founded Judaism. This tradition is implicit in many passages in the prophets (e.g. Isaiah 41:8) and throughout the Talmud (e.g. Yoma 28b) and is borne out by a reading of the book of Genesis. See also:

Were the Israelites monotheistic?
Archaeology

Abraham, tenth-generation descendant of Noah, of Hebrew lineage, was the son of Terah, uncle of Lot, father of Isaac, grandfather of Jacob, and ancestor of the Israelites. His story is in Genesis ch.11 (end), through ch.25. Jewish tradition states that he was the first to teach belief in One God; and it is in his merit that Jews continue to exist (Genesis 18:19, and ch.17).

Abraham came from ancestry that had been aware of God a couple of centuries earlier but had afterwards slipped into idolatry (Joshua 24:2). (See: How did polytheism start.)

By the time of Abraham, the area where he lived was full of pagan cults; they were polytheistic, worshiping multiple deities. Abraham became the first to advance the idea of ethical monotheism: the worship of One God, and the appropriate ethical code of conduct.

Nimrod, the idolatrous tyrant, had brought Abraham's father (Terah) from the Semitic ancestral seat near the confluence of the Balikh and the Euphrates, and instated him in a position of power in his army in the royal Babylonian city of Ur, where Abraham was born. Nimrod persecuted any who would question his idolatrous cult.

The Kuzari (Rabbi Judah HaLevi, 1075-1141) states that Abraham was gifted with high intelligence; and, as Maimonides (1135-1204) describes, Abraham didn't blindly accept the ubiquitous idolatry. The whole populace had been duped, but the young Abraham contemplated the matter relentlessly, finally arriving at the conclusion that there is One God and that this should be taught to others as well. This is what is meant by his "calling out in the name of the Lord" (Genesis ch.12).

As a young man, he remonstrated with passersby in public, demonstrating to them the falsehood of their idols; and our tradition tells how he was threatened and endangered by Nimrod.
Subsequently, Terah relocated to Harran; and it is here that Abraham began to develop a circle of disciples (Rashi commentary, on Genesis 12:5).

Later, God told Abraham in prophecy to move to the Holy Land, which is where Abraham raised his family.
He continued his contemplations, eventually arriving at the attitudes and forms of behavior which God later incorporated into the Torah given to Moses. (See: Thirteen basic Jewish beliefs)

Abraham became the greatest thinker of all time. His originality, perseverance, strength of conviction, and influence, cannot be overestimated.

Abraham, with God's help, trounced the supremacy of the evil Nimrod.

He received God's promise of inheriting the Holy Land (Genesis ch.13).

He strove to raise a family (Genesis ch.15, 17, and 24) which would serve God (Genesis 18:19); and God eventually blessed his efforts, granting him numerous descendants (ibid., ch.16, 21 and 25), in keeping with His promise (Genesis ch.17).

Abraham founded the Jewish people and lived to see his work live on in the persons of Isaac and Jacob; and he taught many other disciples as well (Talmud, Yoma 28b).

He saved the population of the south of Canaan from invading foreign kings (Genesis 14); and he was feared by neighboring kings (ibid., ch.12 and 20).

Abraham gave tithes (Genesis ch.14), entered into a covenant with God (Genesis ch.15 and 17), welcomed guests into his home (Genesis ch.18) unlike the inhospitable Sodomites (Genesis ch.19), prayed for people (Genesis ch.18), rebuked others when necessary (Genesis ch.20), eulogized and buried the deceased (Genesis ch.23), and fulfilled God's will unquestioningly (Genesis ch.22).

He became renowned as a prince of God (Genesis 23:6).

The gravesite of Abraham, Isaac and Jacob and their wives (Genesis 49:29-32) is located in Hebron and has been known and attested to for many centuries.

All of the above practices of Abraham were based upon the ways of God, which Abraham comprehended through his contemplations. These, and similar personality traits, were the teachings of Abraham and his descendants (unlike idolatry, which had tended to go hand in hand with cruel, licentious and excessive behavior, since the caprices which were narrated concerning the idols were adopted as an excuse to imitate those types of behavior). (See: Cruelties of the polytheists)

It is therefore clear why God expresses His love for Abraham (Isaiah 41:8) and calls Himself the God of Abraham (Genesis 26:24), and says that Abraham obeyed Him fully (Genesis 26:5). And this is why Abraham is credited with having begun the religion which became known as Judaism. (However, Abraham and his descendants observed their traditions voluntarily, until the Giving of the Torah to Moses 3325 years ago, when God made it obligatory.)

Answer 10

Tradition states that Abraham (18th century BCE) founded Judaism, and Moses later received the Torah from God.

Abraham, tenth-generation descendant of Noah, of Hebrew lineage, was the son of Terah, uncle of Lot, father of Isaac, grandfather of Jacob, and forefather of the Israelites. His story is in Genesis ch.11 (end), through ch.25. Jewish tradition states that he was the first to actively spread belief in One God; and it is in his merit that Jews continue to exist (Genesis 18:19, and ch.17).

• Link: Abraham's Hebrew ancestry
  

Abraham came from ancestry that had been aware of God a couple of centuries earlier but had afterwards slipped into idolatry (Joshua 24:2).

By the time of Abraham, the area where he lived was full of pagan cults; they were polytheistic, worshiping multiple deities.

• Link: How polytheism began
  

Abraham became the first to advance the idea of ethical monotheism: the worship of One God, and the appropriate ethical code of conduct.

Nimrod, the idolatrous tyrant, had brought Abraham's father (Terah) from the Semitic ancestral seat near the confluence of the Balikh and the Euphrates, and instated him in a position of power in his army in the royal Babylonian city of Ur, where Abraham was born. Nimrod persecuted any who would question his idolatrous cult.

The Kuzari (Rabbi Judah HaLevi, 1075-1141) states that Abraham was gifted with high intelligence; and, as Maimonides (1135-1204) describes, Abraham didn't blindly accept the ubiquitous idolatry. The whole populace had been duped, but the young Abraham contemplated the matter relentlessly, finally arriving at the conclusion that there is One God and that this should be taught to others as well. This is what is meant by his "calling out in the name of the Lord" (Genesis ch.12).

As a young man, he remonstrated with passersby in public, demonstrating to them the falsehood of their idols; and our tradition tells how he was threatened and endangered by Nimrod.
Subsequently, Terah relocated to Harran; and it is here that Abraham began to develop a circle of disciples (Rashi commentary, on Genesis 12:5).

Later, God told Abraham in prophecy to move to the Holy Land, which is where he raised his family.

He continued his contemplations, eventually arriving at the attitudes and forms of behavior which God later incorporated into the Torah given to Moses.

Abraham became the greatest thinker of all time. His originality, perseverance, strength of conviction, and influence, cannot be overestimated.

Abraham, with God's help, trounced the supremacy of the evil Nimrod.

He received God's promise of inheriting the Holy Land (Genesis ch.13).

He strove to raise a family (Genesis ch.15, 17, and 24) which would serve God (Genesis 18:19); and God eventually blessed his efforts, granting him numerous descendants (ibid., ch.16, 21 and 25), in keeping with His promise (Genesis ch.17).

Abraham founded the Jewish people and lived to see his work live on in the persons of Isaac and Jacob; and he taught many other disciples as well (Talmud, Yoma 28b).

He saved the population of the south of Canaan from invading foreign kings (Genesis 14); and he was feared by neighboring kings (ibid., ch.12 and 20).

Abraham gave tithes (Genesis ch.14), entered into a covenant with God (Genesis ch.15 and 17), welcomed guests into his home (Genesis ch.18) unlike the inhospitable Sodomites (Genesis ch.19), prayed for people (Genesis ch.18), rebuked others when necessary (Genesis ch.20), eulogized and buried the deceased (Genesis ch.23), and fulfilled God's will unquestioningly (Genesis ch.22).

He became renowned as a prince of God (Genesis 23:6).

The gravesite of Abraham, Isaac and Jacob and their wives (Genesis 49:29-32) is located in Hebron and has been known and attested to for many centuries.

• Link: Archaeology
  

All of the above practices of Abraham were based upon the ways of God, which Abraham understood through his contemplations. These, and similar personality traits, were the teachings of Abraham and his descendants (unlike idolatry, which had no moral character; with worship of the gods accompanied by things such as human sacrifice, "sacred" prostitution, and animal worship).

• Link: Pagan practices
  

It is therefore clear why God expresses His love for Abraham (Isaiah 41:8) and calls Himself the God of Abraham (Genesis 26:24), and says that Abraham obeyed Him fully (Genesis 26:5). And this is why Abraham is credited with having begun the religion which became known as Judaism. (However, Abraham and his descendants observed their traditions voluntarily, until the Giving of the Torah to Moses 3325 years ago, when God made it obligatory.)