John 7:21

I have done one work — i.e., the one conspicuous work of healing the infirm man on the Sabbath day, which He did at His last visit to Jerusalem. We have already had a reference to other works in John 2:23, and He Himself refers to His many good works in John 10:32.

Ye all marvel. — This answer is addressed to the multitude who said “Thou hast a devil,” when He spoke of the intention to kill Him. This work on the Sabbath day, which provoked the deadly hostility of the hierarchy (John 5:16; John 5:18), was cause of wonder to them all. They, too, though not in the same degree, were led by it to take a hostile position.