Hi, I'm Annelise, writing from Sydney Australia. I wanted to join this forum because I'm curious about the Islamic understanding of Judaism, and thought it would be helpful to ask my questions firsthand from Muslims. I come from a Christian background but was challenged about a year ago by the Jewish understanding, so while I'm not Jewish I do believe what they say about who God is and how He has revealed Himself. I also have some Muslim friends from university whom I respect a lot and who I know have a close relationship with Him. I'm trying to get a wide range of opinions and responses on some issues. I'll number them for clarity, but in a way they build on each other as one question 
1. I know Muslims believe that the Torah came from God but the manuscripts and traditions were changed, so that what the Jews had in the time of Muhammed was no longer the truth God had revealed to the Jewish people. If you do believe that the covenant God made with the Jews was given on the basis of their experience when they came out of slavery in Egypt and He gave His law to them at the mountain, what exactly do you think that covenant/promise was? What were its conditions? And what were the methods that He put in place to make sure that law and their testimony about Him could be preserved for the later generations?
2. In my experience, Christians usually ask Jews to accept Jesus as the Messiah (etc.) based on the current Jewish scriptures, but for Muslims it's different. You believe that the Jewish text of the Bible is corrupted. The reality is that Jews can't accept the Qur'an on the basis of the Torah that they currently have because it contains certain promises and instructions about how to know God in their covenant law and relationship, which they would have to let go of to join Islam. Of course, if the text has been changed then it's not an issue. But this is what I wonder. If Jews can only accept Islam by deciding that there are flaws in the written Torah and the Jewish tradition, and then they might come to Islam for the reasons that anyone else in the world might do so, then why were Jews commanded by the Qur'an to accept Islam on the basis of the knowledge they already had?
3. I don't know how you'll answer the question (2) above, but I can make a guess. It might be possible to say that maybe Jews had corrupted traditions and scriptures, but nonetheless their religions still had a true understanding of some things; a separate, deeper, and innate sense of God's reality, His unity, the way He deserves to be worshipped, and what is truly good or moral. In that way the Qur'an could appeal to something that they thought Jews and Christians already knew while also contradicting the 'shallower' details of their faith claims. I think that the Jewish response to this answer would be that the commandments are fundamentally important in Judaism as a legal covenant religion. If they haven't been preserved accurately, then there is no way of making decisions about new revelations on the basis of the preceding covenant. If this were how the conversation went, what would be the next response from an Islamic perspective?
4. Imagine if a claimant to prophecy came this year and said that Islam was a true revelation from God but that its prophet had slightly, accidentally, added to the message he received before it was written down. Such a new religion might suggest that even though most of the Qur'an was accurate, it wasn't God's final revelation, and some was not from God... but Muslims must still accept the new claim on the basis of the knowledge of God that they already have. If this happened, how would Islam respond to such a claim? What would make you feel confident to ignore it, even if that religion said you needed to accept it in order to continue knowing God?
Thanks so much for reading, and I hope that my way of thinking about these questions is clear enough. I would love to hear any response, simple or in depth, to the perspective I have about what the first Muslims were asking Jews to do, to give up, and to accept. I look forward to meeting you and gaining broader clarity in these things. Blessings,
Annelise

1. I know Muslims believe that the Torah came from God but the manuscripts and traditions were changed, so that what the Jews had in the time of Muhammed was no longer the truth God had revealed to the Jewish people. If you do believe that the covenant God made with the Jews was given on the basis of their experience when they came out of slavery in Egypt and He gave His law to them at the mountain, what exactly do you think that covenant/promise was? What were its conditions? And what were the methods that He put in place to make sure that law and their testimony about Him could be preserved for the later generations?
2. In my experience, Christians usually ask Jews to accept Jesus as the Messiah (etc.) based on the current Jewish scriptures, but for Muslims it's different. You believe that the Jewish text of the Bible is corrupted. The reality is that Jews can't accept the Qur'an on the basis of the Torah that they currently have because it contains certain promises and instructions about how to know God in their covenant law and relationship, which they would have to let go of to join Islam. Of course, if the text has been changed then it's not an issue. But this is what I wonder. If Jews can only accept Islam by deciding that there are flaws in the written Torah and the Jewish tradition, and then they might come to Islam for the reasons that anyone else in the world might do so, then why were Jews commanded by the Qur'an to accept Islam on the basis of the knowledge they already had?
3. I don't know how you'll answer the question (2) above, but I can make a guess. It might be possible to say that maybe Jews had corrupted traditions and scriptures, but nonetheless their religions still had a true understanding of some things; a separate, deeper, and innate sense of God's reality, His unity, the way He deserves to be worshipped, and what is truly good or moral. In that way the Qur'an could appeal to something that they thought Jews and Christians already knew while also contradicting the 'shallower' details of their faith claims. I think that the Jewish response to this answer would be that the commandments are fundamentally important in Judaism as a legal covenant religion. If they haven't been preserved accurately, then there is no way of making decisions about new revelations on the basis of the preceding covenant. If this were how the conversation went, what would be the next response from an Islamic perspective?
4. Imagine if a claimant to prophecy came this year and said that Islam was a true revelation from God but that its prophet had slightly, accidentally, added to the message he received before it was written down. Such a new religion might suggest that even though most of the Qur'an was accurate, it wasn't God's final revelation, and some was not from God... but Muslims must still accept the new claim on the basis of the knowledge of God that they already have. If this happened, how would Islam respond to such a claim? What would make you feel confident to ignore it, even if that religion said you needed to accept it in order to continue knowing God?
Thanks so much for reading, and I hope that my way of thinking about these questions is clear enough. I would love to hear any response, simple or in depth, to the perspective I have about what the first Muslims were asking Jews to do, to give up, and to accept. I look forward to meeting you and gaining broader clarity in these things. Blessings,
Annelise