In chapter 11 of your book Heaven, under the subhead “Of the Dust of the Earth,” you write, “When viewed in context, ‘dust of the earth’ seems to refer to more than the first man’s origin, and at points appears to be associated with mortality and corruption. The man of dust, who was human only, succumbed to temptation; the man from Heaven, who is both human and divine, could not and did not.”
Does the statement that “the man from Heaven, who is both human and divine, could not and did not” mean Jesus had no free will? In other words, if Jesus could not succumb to temptation, does that mean He didn’t even have the option of sinning?
Any person who acts in keeping with his nature is exercising free will. So we can say “a sinner can’t help but sin,” but that doesn’t mean he doesn’t have free will. He will say no to some sins and yes to others. But having a sin nature means he will exercise his free will to sometimes sin.
Christ had and has free will, but it too is governed by His nature. Because He is holy by nature, He could not sin, for as God He is incapable of sinning. It is not in His nature to do so. When His divine and human natures were combined into one person, He had free will but it was not in Him to sin. I deal further with the question of whether Jesus had a sin nature here.
Here John Piper gives an excellent answer to the question of whether Jesus could have sinned.
This is a good resource on what God cannot do. Here’s a paragraph from it:
The only thing that God cannot do is act contrary to His own character and nature. For example, Titus 1:2 states that He cannot lie. Because He is holy (Isaiah 6:3; 1 Peter 1:16), He cannot sin. Because He is just, He cannot merely overlook sin. Because Christ paid the penalty for sin, He is now able to forgive those who will turn to Christ (Isaiah 53:1-12; Romans 3:26).