John Calvin Commentary Acts 26:8

"Why is it judged incredible with you, if God doth raise the dead?" — Acts 26:8 (ASV)

Indeed, I do not doubt that he proved, both by reason and also by testimonies of Scripture, what he taught concerning the resurrection and the heavenly life. But for good reasons he calls back those to whom he speaks to the power of God, so that they do not judge it according to their own weak capacity.

For nothing is harder for men to grasp than that men’s bodies will be restored after they have been consumed. Therefore, since it is a mystery far surpassing human understanding, let the faithful remember how far the infinite power of God reaches, and not what they themselves comprehend, as the same Paul teaches in the third chapter of Philippians (Philippians 3:21).

For when he has said that our vile bodies will be made like the glorious body of Christ, he adds immediately, according to the mighty working whereby he is able to subdue all things to himself.

But men, for the most part, do injustice to God, as they do not want His arm to reach any further than their understanding and reason can reach; so that, as much as in them lies, they would desire to restrain the greatness of His works (which surpasses heaven and earth) within their narrow limits. But, on the other hand, Paul commands us to consider what God is able to do, so that, being lifted up above the world, we may learn to conceive the faith of the resurrection, not according to the weak capacity of our mind, but according to His omnipotence.