A.T. Robertson Commentary John 7:40

"[Some] of the multitude therefore, when they heard these words, said, This is of a truth the prophet." — John 7:40 (ASV)

Some of the multitude (εκ του οχλου). Τινες (some) to be supplied, a common Greek idiom.

Of a truth (αληθως). "Truly." See 1:47.The prophet (ο προφητης). The one promised to Moses (Deuteronomy 18:15) and long expected. See on John 1:21. Proof of the deep impression made by Jesus.