John Calvin Commentary John 20:24

"But Thomas, one of the twelve, called Didymus, was not with them when Jesus came." — John 20:24 (ASV)

But Thomas, one of the twelve. The unbelief of Thomas is related here, so that by it the faith of the godly may be more fully confirmed. He was not only slow and reluctant to believe, but even obstinate.

His slowness to understand was the reason Christ again permitted them both to see and to feel Him, in the same manner as before. In this way, further proof of Christ’s resurrection was given, not only to Thomas but also to us.

Besides, the obstinacy of Thomas is an example to show that this wickedness is almost natural to all people: to hold themselves back of their own accord when the entrance to faith is opened to them.