John Calvin Commentary John 4:13

"Jesus answered and said unto her, Every one that drinketh of this water shall thirst again:" — John 4:13 (ASV)

Every one that drinketh of this water. Though Christ perceives that He is doing little good, and even that His instruction is treated with mockery, He proceeds to explain more clearly what He had said. He distinguishes between the use of the two kinds of water: that the one serves the body, and only for a time, while the power of the other gives perpetual vigor to the soul.

For, as the body is liable to decay, so the aids by which it is supported must be frail and transitory. That which quickens the soul cannot but be eternal. Again, the words of Christ are not at variance with the fact that believers, to the very end of life, burn with desire for more abundant grace.

For He does not say that, from the very first day, we drink so as to be fully satisfied. He only means that the Holy Spirit is a continually flowing fountain, and therefore, there is no danger that those who have been renewed by spiritual grace will be dried up.

Therefore, although we thirst throughout our whole life, it is certain that we have not received the Holy Spirit for only a single day, or for any short period, but as a perennial fountain, which will never fail us. Thus believers thirst, and keenly thirst, throughout their whole life; yet they have an abundance of quickening moisture. For however small the measure of grace they have received, it gives them perpetual vigor, so that they are never entirely dry. When, therefore, He says that they will be satisfied, He does not contrast this with Desire but only with Drought.

Shall be a fountain of water springing up into eternal life. These words express still more clearly the preceding statement; for they denote a continual watering, which maintains in them a heavenly eternity during this mortal and perishing life. The grace of Christ, therefore, does not flow to us for a short time but overflows into a blessed immortality, for it does not cease to flow until the incorruptible life which it commences is brought to perfection.