Maimonides (Rambam) on Jesus and Mohamed and why G-d has allowed religions they founded to spread
In his Mishneh Torah Maimonides (Rambam) delves into Jesus’ failed attempt to “fulfill the vision” as a would be messiah, speculates on what could be behind G-d’s permitting both Christianity and Islam to take over the world, in particular how G-d may be using these false religions to prepare the world for the true Jewish Messiah and the real redemption of humanity:
“Jesus of Nazareth who aspired to be the Moshiach and was executed by the court was also spoken of in Daniel’s prophecies [Daniel 11:14], “The renegades among your people shall exalt themselves in an attempt to fulfill the vision, but they shall stumble.“
Can there be a greater stumbling block than [Christianity]? All the prophets spoke of Moshiach as the redeemer of Israel and their savior, who would gather their dispersed ones and strengthen their [observance of] the mitzvos. In contrast [the founder of Christianity] caused the Jews to be slain by the sword, their remnants to be scattered and humiliated, the Torah to be altered, and the majority of the world to err and serve a god other than the L-rd.
Nevertheless, the intent of the Creator of the world is not within the power of man to comprehend, for [to paraphrase Yeshayahu 55:8] His ways are not our ways, nor are His thoughts our thoughts. [Ultimately,] all the deeds of Jesus of Nazareth and that Ishmaelite [i.e. Mohammed] who arose after him will only serve to pave the way for the coming of Moshiach and for the improvement of the entire world, [motivating the nations] to serve G-d together, as it is written [Zephaniah 3:9], “I will make the peoples pure of speech so that they will all call upon the Name of G-d and serve Him with one purpose.
How will this come about? [meaning, in the future, not that the nations which follow these religions already serve G-d] The entire world has already become filled with talk of [the supposed] Messiah, as well as of the Torah and the mitzvos. These matters have been spread among many spiritually insensitive nations, who discuss these matters as well as the mitzvos of the Torah. Some of them [i.e. the Christians] say: “These commandments were true, but are not in force in the present age; they are not applicable for all time.” Others [i.e. the Moslems] say: “Implied in the commandments are hidden concepts that cannot be understood simply; the Messiah has already come and revealed them.”
When the true Messiah king will arise and prove successful, his [position becoming] exalted and uplifted, they will all return and realize that their ancestors endowed them with a false heritage; their prophets and ancestors cause them to err.