I am amazed at Muslims who ask " where could have Muhammad heard this or that?", as if he dropped down from heaven…fact is he was surrounded by people who read the previous scriptures, including his teacher Waraqa Ben Nawfal who used to translate scriptures into Arabic and who knew Muhammad for many years before his death.
As to the Islamic response to Biblical corruption charge, i can paraphraze it as follows : the Bible is corrupt even if i cannot prove it, because the Quran says so".
This cannot be even called an argument…besides, many people created books and called them the word of God…how are Muslims any different from all the people who follow different books all the while claiming the Bible is corrupt? no difference in belief, but a common charge of Biblical corruption and all are certain their book is from God, regardless where their prophets took their ideas from, as long as they “like” them.
This “non-argument” cannot be answered because the other party is not using reason but faith in something…faith that Islam is correct because it has too many adherents…because it is “easy”…because it is about “One God”…because the book is “preserved”…because it tells you what to eat and how to sleep and dress up…because “i cany understand the Trinity”, because i refuse to believe Jesus is more than a human…in other words, you “find” yourself in Islam, and hence you start “defending” it, but when rational arguments start, we hear no answers, or conflicting ones, or inconsistent ones…whether about the crucifixion of Jesus, the virgin birth of Jesus, the title Son of God, the Trinity concept, or the Bible corruption claim…rarely do Muslims realize that the Quranic refutations are based on the misunderstading of a human, rather than an all-knowing deity…rarely do Muslims know that every single Quranic passage is found in here or there as if Allah’s role is to pick and choose what he was unable to preserve, though he said his word is preserved…talk about mass confusion of history and theology from an all-knowing deity.