Why was moses important?

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.

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).

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What problems did Moses face and overcome?

How did Moses know he was an Israelite?

1) In those days, Israelite custom was to nurse babies for up to four years. Since it was his own mother who nursed him (Exodus 2:8-9), his family had plenty of time to teach him before he was returned to Pharaoh's daughter (Exodus 2:10) to live in the palace.
2) Moses was not a prisoner in the royal palace. He came and went as he pleased (Exodus 2:11 and 2:13) and sought out his people (ibid).

Did Moses ever sin or make a mistake?

1) The claim to infallibility is a sure sign of megalomania and prevarication. The Hebrew Bible, because of its Divine origin, kowtows to no man, and prominently spotlights the faults of even its greatest protagonists. In this regard it is unique in ancient literature.

2) Moses' sin is mentioned (Numbers 20:12 and 24) again and again (Numbers ch.27, Deuteronomy ch.32). He struck the rock which was, by a miracle of God, made into a source of water (Numbers ch.20). He was supposed to speak to the rock instead (ibid). Striking the rock served to slightly diminish the miracle.

It should be self-understood that this criticism of Moses is only in proportion to his greatness. In the final analysis, he remained the most godly person who ever lived (Deuteronomy ch.34).