¹ with you is the fountain of life, in your light we see light.

with you is the fountain of life,

David is clearly speaking about Christ, for Christ is the light, which is the light of men.

In him was life; and the life was the light of men. John 1:4
Jesus said to her, "I am the resurrection, and the life..." John 11:25
Then Jesus said to him, "I am the way, the truth, and the life;..." John 14:6
"...He who follows me shall not walk in darkness, but shall have the Light of Life." John 8:12

And in Jesus is the fountain of life.

And he said to me, "It is done. I am the Alpha and the Omega, the beginning and the end. I will give to him who is thirsty the fountain of the water of life freely. Rev 21:6, Rev 22:13-16

He who believes on me, as the scripture has said, 'out of his belly shall flow rivers of living water.' John 7:38
But whoever drinks of the water that I give him shall never thirst; but the water that I shall give him will be a well of water springing up in him to everlasting life. John 4:14.

in your light we see light.

God is light. Jesus is the light of the world [all men], given to every man who comes into the world so that they might believe. Jesus dwells in unapproachable light. In heaven there is no sun or moon, for the Jesus is the light. When man continually listens to and obeys the voice of the Lord, God causes His light to shine in a man's heart, which reveals the glory of God in the face of Christ Jesus. When a man is purified and the light arises in his heart, then he walks by the light of God, not the sun or moon; being made partakers of the inheritance of the saints in the light. Col 1:12.

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