When were they passed to a messenger? It was when they engaged in idol worship. From where is it derived? For this is what the Holy One blessed be He said to Moses: “Go, lead the people…[behold, My angel will go before you]” (Exodus 32:34).9This verse was stated in the aftermath of the sin of the Golden Calf.
Moses said: “If Your presence does not go, do not take us up from here” (Exodus 33:15). Moreover, Moses said to the Holy One blessed be He: Master of the universe, what is the difference between us and the idolaters? We have prophets and they have prophets.10This is based on Exodus 33:16, where Moses continues to plead that God Himself lead Israel, arguing that if He does not do so there will be no difference between Israel and other nations.
We have a guardian angel and they have a guardian angel. Rabbi Levi said: The Holy One blessed be He abolished two good benefits from the idolaters such that prophets would not arise for them and that Israel would not be passed to a guardian angel all the days of Moses. When Moses died, that guardian angel returned to his place, for Joshua saw him, as it is stated: “It was when Joshua was in Jericho.… He said: No, for I am commander of the host of the Lord; now I have come” (Joshua 5:13–14). That is why it is stated: “Behold, I am sending an angel before you.”