What is the wisdom behind the descent of the Messiah (Jesus), and will he lead the Muslims?

Perhaps the wisdom behind thelesser descent of Jesus (peace be upon him) is to refute the Jews' claim that they killed and crucified him, to fulfill Allah's promise, to confirm the prophethood of Muhammad, and as a miracle for Jesus. The descent of Jesus (peace be upon him) does not necessarily mean that he will be the leader of the Muslims, as it has been stated in authentic hadiths that he will descend while the Imam of the Muslims is from among them, and that he will refuse the imamate, saying: "Indeed, some of you are leaders over others, as an honor for this Ummah." There is no problem in the imamate of the lesser in the presence of the superior.