Christ , after all, was a human being.  As it says in Heb. 2:18: “For in that He Himself had suffered, being tempted, He is able to succor them that are tempted.”   The sin or the being tempted that you refer to does not mean that he did give in to temptation or the act of sinning, it just means that he was capable of doing what the “self” wanted, and that is supposed to be sinful.  Self-interested thinking leads to a desire for personal gain.  This is called temptation.  You could say that Christ wanted people to believe in what he was saying.  At times he got discouraged, but he did not quit.  Wanting people to believe was his self-interest.    Sin is in every one but that does not make people sinners, it is part of their human condition.   If Christ was not created as a human being he could not save mankind.