The Prophets - 21:29 "Whoever of them says, "I am a god beside Him,"We will punish him with Hell; thus do We reward the wrongdoers."
Jesus, whom the Christians took as a god besides Allah, did not call the people to him, saying: "Serve me after Allah":
The Table Spread/5:116 "Allah will say: "O Jesus son of Mary, did you say to the people, ´Take me and my mother as gods besides Allah´?"(Jesus) will reply: "You are great, it is not befitting me to say what I have no right to say. You would have known if I had said such a thing. You know what I think, but I do not know what you think. You know all mysteries."
The Table Spread/5:117 I said to them nothing but what You commanded me: ´Serve Allah, my Lord and your Lord.´ I was a witness to them as long as I was among them, and when You took my life, You became a watcher over them. You are the Witness of all things.

The Family Of Imran/3:79 "No man to whom Allah has given the Book, wisdom and prophethood calls the people to Him, saying: "Serve me after Allah". Rather, he says, "Be servants devoted to your Lord in accordance with the Book which you have learned and taught"."

The Prophets/21:25 "We did not send a messenger before you except that We revealed to him, "There is no god but Me; serve Me alone."