John 4:36

He that reapeth receiveth wages, and gathereth fruit unto life eternal; he that soweth and he that reapeth may rejoice together.

These words were spoken by the Lord during the interval before the arrival of the multitude. This is an extension of the metaphor of the harvest, there never being a harvest without a sowing and reaping. The great reward is the gathering of fruit unto life eternal, in the joy of which both sowers and reapers shall rejoice together.

He that reapeth receiveth wages ... It is not known if Jesus was here thinking of the reaping that Philip the evangelist would do in Samaria (Acts 8:4-13), or if he was thinking of the multitudes who would believe that very day (John 4:41), or perhaps of both.

Rejoice together ... Sowers and reapers alike rejoice in the harvest of the gospel; and their doing so together would indicate that, in the instance in hand, sowing and reaping would occur in the closest proximity of time, as it did on that occasion. Jesus was the sower who planted the word in the heart of the woman; but the fruit was coming over the fields at that very moment; and the apostles, who hardly knew that any sowing had taken place, were about to participate in the reaping. Evidently, the Lord intended in these words to show the equal importance of both sowing and reaping, both being necessary, and to show that the reaper should always, in humility, remember the one who had sown. That Christ was indeed the sower here is indicated by "He that soweth the good seed is the Son of man" (Matthew 13:37).