(1) Ezra is not the one referred to in Qur'an. The one referred to in Qur'an is Uzayr (not to be Ezra but Azariah), mentioned in the book of Daniel as Abednego.
(2) The verse (Q, 9:30) refers to those Jews; who lived in Arabia during the time of prophet Muhammad; who did or do call Uzayr son of God, rather than the overwhelming majority who revere him as a scribe. Accordingly, this verse referred to a specific group of Jews who lived in Arabia during the time of prophet Muhammad. In the Qur'an, the verses do not specify to particular groups. For example, when it speaks of the Christians worshiping Christ as the son of God, it doesn't specifically say Trinitarian Christians, instead just using the generic term Christian. Therefore, it obviously does not refer to all Christians, such as Unitarians, who call Christ a prophet rather than son of God. Refer to link below.
(3) Refer to the attached link, authored by Westerners, to know that in history there were a group of Jews who considered Uzayr (not to be Ezra but Azariah) as son of God.
[Debate on whether Ezra is the proper translation of Uzayr in Q: 9:30 moved to Discussion Section and Related Question.]
All people are the children of HaShem according to Judaism, this is not literal.
Christianity: Son of God (Messiah) Islam: Prophet Judaism: False messiah
In Judaism, Yahweh is considered to be the one and only God, and there is no concept of Him having a son. Christianity, however, believes that Jesus is the Son of God.
All Christianity - medieval, ancient, modern and otherwise - differs from Judaism and Islam in worshiping Jesus of Nazareth as the Son of God, Lord and Savior.
God for the religions Judaism, Christianity, and Islam is the same God; called in Arabic Allah. God is the one and only one God with no partner and no companion. However, some Christians consider God as composed of three species Son, Father, and soul (the Trinity).
Judaism does believe in god but have rejected his son jesus christ. Christianity believes in god and jesus christ
Muslims viewChristians altered the original message of their prophets in calling for worshiping God as the one and only one God with no partner, no son, no companion, no associate, and no equivalence and some of them claimed that Jesus is son of God and others claimed that Aliazer is son of God. Muslims do not believe that God has a son. Refer to question below.Jewish ViewAs Christianity was based on the rejection of Judaism, the two religions have virtually nothing in common. The closest commonality would be that the Christian Old Testament was based on the Tanach (Jewish Bible) but the OT was altered to support the teachings of Christianity.In truth, Judaism and Islam have far more in common with each other than Judaism does with Christianity.
The three religions should have the same faith based on monotheism; that is full submission (Islam in Arabic) to God the one and only one God with no partner, no companion, no son, no associate, and no resemblance. The belief of some Christians that Jesus is God or son of God is not from the original Christianity and never Jesus called for worshiping him as God or son of God.
Christians worship the god of the old testament and Jesus. Jesus is worshipped by Christians as the son of GOd. This being said, other than both religions gather in groups to pray, there are no similarities in prayer services between Judaism and Christianity.
A monotheistic religion has only one god. Examples of monotheistic religions are Judaism and Islam. Christianity is generally defined as a monotheistic religion even though the Christian god is tripart (God the Father, God the Son and God the Holy Spirit). Interestingly, although they follow different prophets, Judaism, Islam and Christianity worship the same god.
Truly Christianity began in Judaism, but if you're asking why did they split up, it is because Christians believe Jesus is the Messiah, aka son of God, Jews claim that he is not.
All God religions are considered monotheistic. Namely Judaism, Christianity, and Islam. Islam in its universal meaning is full submission to Allah (or God in English and same God worshiped in Judaism and Christianity) as the one and only one God with no partner, no companion, no son, no father, no associate, and no equivalence.