John Gill 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)

Many of the people therefore
Of the common people, and it may be chiefly those that came out of the country:

when they heard this saying ;
or discourse of Christ, on the last and great day of the feast, relating to the large measure of grace, and the effusion of the Spirit on him, that believed:

said, of a truth this is the prophet ;
spoken of in (Deuteronomy 18:15) , which some understood not of the Messiah, but of some extraordinary prophet distinct from him, who should come before him, or about the same time; or they imagined he was one of the old prophets raised from the dead, whom they also expected about the times of the Messiah: or their sense might only be, that he was a prophet, which was true, though not all the truth; they had some knowledge, though but small; and they spoke of him, though but as children in understanding.