"living water" and
"light of the world"
The Feast of Tabernacles was a joyful feast often looked upon as a holiday. It included giving a tithe to the Lord for they were not to "appear before the Lord empty-handed" (Dt. 16.16). They built small booths out of branches and palm leaves to remind them of their temporary dwelling here on earth. These booths were to have fruit interwoven in them in thanksgiving for the harvest that came. In the same way we are expected to bear fruit before the Lord.
There were special ceremonies for drawing water from the Pool of Siloam, during which the priests repeated Isaiah 12.3, "Therefore with joy you will draw water from the wells of salvation." On the final day of the feast, special prayers were offered for rain for the coming year. It was on this day that Jesus declared in the Temple "If anyone thirsts, let him come to Me and drink. He who believes in Me, as the Scripture has said, out of his heart will flow rivers of living water" (Jn. 7.37-38). In other words, not just water collected in cisterns that may become stagnant, but water that is moving, living water. We can easily become like the people Jeremiah warned about: "For My people have committed two evils" They have forsaken Me, the fountain of living waters, and hewn for themselves cisterns - broken cisterns that can hold no water." (Jer. 2.13).
As the water ceremony occurred at night, there was also the impressive ceremony of lights that accompanied it. On the day after the Feast, the eighth day, which was also a Sabbath, Jesus proclaimed "I am the light of the world. He who follows Me shall not walk in darkness, but have the light of life." (Jn. 8.12). In Revelation, the final fulfillment of this ceremony is revealed as John witnesses the New Jerusalem coming down from heaven. "And the city had no need of the sun, neither of the moon, to shine in it: for the glory of God did lighten it, and the Lamb is the light thereof." (Rev. 21.23). The future fulfillment of this feast may not be far off, as the Lord not only gathers His people, but He also tabernacles in their midst during His Messianic Kingdom "My tabernacle also shall be with them; indeed, I will be their God, and they shall be My people. The nations also will know that I, the Lord, sanctify Israel, when My sanctuary is in their midst forevermore" (Ezek. 37.27-28; Rev. 21.3).