John the Apostle
John 5:12ESV·traditional attribution

They asked him, “Who is the man who said to you, ‘Take up your bed and walk’?”

Matthew Henry Presbyterian @wholebiblehenry

This miraculous cure is not recorded by any other of the evangelists, who confine themselves mostly to the miracles wrought in Galilee, but John relates those wrought at Jerusalem. Concerning this observe, I. The time when this cure was wrought: it was at a feast of the Jews, that is, the passover, for that was the most celebrated feast.

Commenting on John 5:1-16

John Gill Reformed Baptist @doctorgill

Then asked they him,.... Suspecting who had made him whole, and gave him this order: what man is that which said unto thee, take up thy bed and walk? they take no notice of the cure, being unwilling to give any glory to Christ, and still less to spread it; but chose rather that it should be obscured, hid, and unobserved; but they laid hold...

Albert Barnes Presbyterian @notesbybarnes

Verse 12. What man is he, &c. In this verse there is a remarkable instance of the perverseness of men, of their want of candour, and of the manner in which they often look at a subject. Instead of looking at the miracle, and at the man's statement of the manner in which he was healed, they look only at what they thought to be a violation of the law.