John is quoting Isaiah 58:11 where it says, “The Lord will guide you always; He will satisfy your needs in a sun scorched land and will strengthen your frame. You will be like a well-watered garden, like a spring whose waters never fail.” Just as a river flows hundreds and thousands of miles from its source…the River of Life flows from its source, God, to enliven Believers with spiritual and eternal life.
No matter how many animal sacrifices were made in the Temple…they never fully removed the people’s sin. It wasn’t until Jesus Christ gave Himself up as the unblemished Lamb of God that humankind was finally delivered from the guilt and punishment of sin. Hebrews 9:12 says, “He did not enter by means of the blood of goats and calves; but He entered the Most Holy Place once for all by His own blood, having obtained eternal redemption.” God offered His only son, Jesus, to take our place on that Cross. He died as an atonement for our sins…His blood being shed once for all. Which means He only had to died one time, not over and over again like the Temple sacrifices. For it was Jesus that took upon Himself the sins of the entire world that you and I might be redeemed and set free.