Surah 3. Aal-Imran

58That is, "Your Judaism and Christianity came into existence long after the revelation of the Torah and the Gospel, whereas Abraham (God's peace be upon him) had passed away long before those Books were sent down. Now, even a man of ordinary common sense can easily understand that the religion of Abraham could in no sense be Judaism or Christianity. Thus, if Abraham was on the right way and had obtained salvation, as you also believe, then it becomes abundantly clear that one need not follow Judaism or Christianity to be on the Right Way and to obtain salvation." (Also see E.N. 135 and 141, Al-Baqarah.)