Muslims believe in all the true prophets of God. There are two lines of descent from Abraham, one is through Ishmael and the other through Isaac and Jacob. We believe in Isaac, Jacob, Joseph, Moses, Aaron, David, Solomon, Elijah, Elisha, Enoch, Ezra and others. And we believe in Jesus as a prophet of God. The Prophet Muhammad is a descendant of Abraham, Hagar and Ishmael, about 600 years after Jesus.
Some of the prophets were given scriptures by revelations, and they were charged with conveying the message from God to people.
If we believe in the Prophets Moses and Jesus, why are we not Jews or Christians, why do we not follow the Torah and the Gospel?
We believe that with God is a "Book", His message and guidance to mankind. He revealed it incrementally over time through the Prophets. Jews and Christians are considered to be "People of the Book", because part of the "Book" was revealed to them through their prophets and was part of their scriptures.
The first prophet was Adam, and he had only two commandments to worry about: (1) Worship God and (2) Stay away from the tree. Abraham was given the "Scrolls". To Moses was given the Torah, a light and a guidance for the Israelites. To Jesus was given the Gospel, which made clearer the relationship with God, and removed some of the harshness of Judaism, and introduced love and compassion. To Muhammad was given the Quran, which completed the revelation of God's "Book", His message and guidance to mankind.
The scrolls of Abraham are no more, there is no record of their contents.
Part of the Torah was the word of God as given to Moses like the commandments, while some of it is stories and history that are not of Divine origin. After the Babylonians defeated the Israelites, the Temple in Jerusalem was destroyed, the holy vessels and books were seized by the Babylonians, and the Israelites were taken into captivity in Babylon ( in what is now Iraq). After their release from captivity, the Israelites rebuilt the Temple and rewrote the Torah as best they could from memory, as recently as a thousand years before Jesus. The Torah that the Jews have now is not the same exact Torah as given by God to Moses, it has additions, changes and omissions from the original, which explains some of the discrepancies in it.
As regards the Gospel, Jesus and the disciples preached only in Aramaic, which was the common spoken language of the Israelites at that time, while Hebrew was used for formal religious purposes, with Aramaic. The Gospels as we have them today are derived from Greek manuscripts written decades after the ascension of Jesus by persons who were not the disciples of Jesus. There is not a scrap of a manuscript anywhere in the original Aramaic. All that is left is only a few phrases from the original Aramaic, like “Qumi” to Tabitha, the little girl, telling her to get up. What happened to the original words of Jesus? We know for sure that Matthew, Mark, John never ever preached in the Greek, only in the Aramaic, so where is their Aramaic Gospel? They certainly did not write the Gospels that are attributed to them. And Luke was not a disciple of Jesus.
Much of the New Testament contains the words and interpretation of Paul in his preaching to the Greek Gentiles, after the Jews rejected him. The Gospels as recorded in Greek have been influenced by Paul's preaching to the polytheistic Greeks. Later Church leaders selected some Gospels and omitted others for inclusion in the New Testament, and there are variations even between the Catholic and Protestant versions of the Bible.
Even if the full accurate text of the Gospels had existed in Aramaic, much can be lost in translation from a Semitic language like Aramaic to Greek. It would be difficult to convey religious concepts from monotheistic Jewish culture in Aramaic to the polytheistic Greek culture, which had no concept of the One God or of prophets sent by God. The New Testament is not the exact words of Jesus, not only is it not in the original Aramaic, some of what Jesus said has been modified or omitted, and many other words, ideas and concepts, mainly of Paul, have been added to it.
The Quran is exactly as it was revealed to the Prophet Muhammad. How is that possible?