Charles Spurgeon Commentary John 7:39-40

"But this spake he of the Spirit, which they that believed on him were to receive: for the Spirit was not yet [given]; because Jesus was not yet glorified. [Some] of the multitude therefore, when they heard these words, said, This is of a truth the prophet." — John 7:39-40 (ASV)

(But this spoke he of the Spirit, whom those who believe on him should receive: for the Holy Ghost was not yet given; because that Jesus was not yet glorified.) Many of the people therefore, when they heard this saying, said, Of a truth this is the Prophet.

The Prophet about whom Moses spoke.