In God's house, we also share of the fountain of the life of God (Psa. 36:9a). Psalm 36 speaks of the river of God's pleasures and of the fountain of life. In the New Jerusalem, the tree of life is growing in the river of water of life. Thus, the fountain of life in Psalm 36 implies the tree of life growing in the river of the life of God.
Psalm 36:9b says, "In Your light we see light." Thus, in the house of God, we enjoy the river of life, the tree of life, and the light of life. These three things are strongly stressed in the New Jerusalem. Revelation 21 and 22 reveal that the light of the New Jerusalem is God in Christ. Christ is the lamp (Rev. 21:23), and God is the light in the lamp (22:5). The lamp with the light is in the New Jerusalem. This shows us again that God is located. God is located in Christ, and Christ is located in the New Jerusalem, where the Triune God will be the light. In that light, we see light.
It is amazing that in the ancient time, the psalmist, David, could utter such wonderful things in Psalm 36 according to the revelation of the Spirit, not according to his human, natural concept. Psalm 36 reveals the fatness for us to be saturated, the river of life for us to drink, the tree of life for us to share, and the light of life for our living and walking.
This is the enjoyment of God in His house, which is Christ, the church, and the New Jerusalem. Our God is located in these three persons: in Christ, in the church as a corporate person, and in the New Jerusalem as a corporate person. In these three persons, we can enjoy the located God as the fatness to saturate us, the river of life to quench our thirst, to satisfy us; the tree of life to feed us; and the light of life to enlighten us.