According to verse 20 Jesus "was chosen before the foundation of the world." This is a grand truth that we avow with both regularity and passion--and we should--that the sacrifice of Jesus for our sins was God's plan from before the creation of the world. But did you notice that Jesus was "chosen" for this purpose, and that He was chosen according to God's foreknowledge--literally He was "foreknown" (ESV, ASV), "foreordained" (NKJV).
There are many who believe that God's grace is irresistible to those who are elected to salvation. We were predestined to either accept God's offer of salvation to us or we were predestined to reject it. We really have no choice in the matter. Our response to the Gospel was predetermined in eternity past by a sovereign God.
So, my question is this: If Jesus Christ was "chosen before the foundation of the world" to become God's sacrifice for our sins, did He have a choice? Did He have the freedom to choose whether or not He would fulfill God's plan? Was God's predetermined will for Him irresistible? And if His death upon the cross was determined before He ever stepped upon this planet, then can we honestly say it was voluntary? I think we would have to honestly say it was not!
Therefore I am going to say that Jesus did have a choice. That choice was confronting Him as late as the Garden of Gethsemane where He prayed three times that "this cup pass from Me." The cup of which He was referring was the bitter cup of God's wrath for our sins. I believe that Jesus had the choice up until the moment He took up that cross to walk away from His mission. He could have said, "I am not going through with this," and immediately ascended back to the safety of heaven. But (praise God!!) that is not what He did. He chose to take up the cross, taking our sin and our sentence with it, and fulfilled the mission for which He had come into the world. But I believe without any doubt it was His choice--just like I believe that ultimately the decision to accept His payment for our sins is our choice; and that choice in no way infringes upon the sovereignty of God.