Rivers of Living Water by T Austin-Sparks and published by Classics.
Our key Scripture will be found in the Gospel by John, chapter 7, verses 37-39:
“Now on the last day, the great day of the feast, Jesus stood and cried, saying, If any man thirst, let him come unto me, and drink. He that believeth on me, as the scripture hath said, out of him shall flow rivers of living water. 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.”
“Rivers of living water”. John’s comment on those words of Jesus, you note - a comment written long after Jesus uttered the words, with all the full and long experience of the Apostle behind the comment - was: “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.” The first part of that comment gives the key to the meaning and the nature of rivers in all the Scriptures. It is the Holy Spirit. If we take all these references to rivers and wells, springs and flowing water, to which I have just turned you, as symbolic of the Holy Spirit, then we have certain quite simple and clearly defined thoughts of God.