“Jesus answered and said unto them, I have done one work, and ye all marvel.”
King James Version (KJV)
7:21 I did - At the pool of Bethesda: one work - Out of many: and ye all marvelled at it - Are amazed, because I did it on the Sabbath day.
Joh 7:21 I have done one work. He goes back to the cause of the enmity of the rulers, the healing of the impotent man at the pool of Bethesda on the Sabbath day, about eighteen months before. See Joh 5:16.