The water which came out of the rock is the water of life in resurrection. Resurrection denotes something which has been put to death and which is alive again. It also denotes life which springs forth out of something that has passed through death. The living water in Exodus 17 came out of a rock. Why did God cause water to come out of a rock? Since He is almighty, there was no need for Him to use a rock. He could simply have opened the ground and caused living water to spring forth. In the Bible this rock speaks of God’s redemption and Christ’s incarnation. It also speaks of Christ’s humanity and of His death. The water that flowed out of the smitten rock sprang forth after incarnation, human living, and death. It flowed only after these major steps of Christ had been accomplished. The Bible tells us clearly that the rock was Christ. How could Christ, who is God, become a rock? This implies incarnation and human living. In order to be the rock, Christ had to become incarnated and live among men for a period of time. Eventually, when He was on the cross, He was smitten by the authority of God’s law. Hence, 17:6 is a profound verse. It implies Christ’s incarnation, human living, and death.
The water of life is in resurrection. Actually, the water itself is resurrection. This means that the Spirit, signified by the flowing water, is resurrection. Resurrection is the Triune God, the Father as the source, Christ the Son as the course, and the Spirit as the flow….This water has passed through incarnation, human living, and death. Because this water is in resurrection, the more we drink it, the more we are out of our natural condition and are triumphant over hardships and difficulties. This living water delivers us from the world and from every kind of negative thing. (Witness Lee, Life-study of Exodus, msg. 42)