"Here we saw the tree of life and the throne of God. Out of the throne came a pure river of water, and on either side of the river was the tree of life. On one side of the river was a trunk of a tree, and a trunk on the other side of the river, both of pure, transparent gold. At first I thought I saw two trees. I looked again, and saw that they were united at the top in one tree. So it was the tree of life on either side of the river of life. Its branches bowed to the place where we stood, and the fruit was glorious; it looked like gold mixed with silver. EW 17.1"
"And he shewed me a pure river of water of life, clear as crystal, proceeding out of the throne of God and of the Lamb."
The EGW passage is a direct and detailed expansion of Revelation 22:1, describing the river of life proceeding from the throne of God. The tree of life on either side of the river is also a key element present in both texts.
"up our greatest trials, but they looked so small compared with the far more exceeding and eternal weight of glory that surrounded us that we could not speak them out, and we all cried out, “Alleluia, heaven is cheap enough!” and we touched our glorious harps and made heaven's arches ring. EW 17.2"
"For our light affliction, which is but for a moment, worketh for us a far more exceeding and eternal weight of glory;"
The EGW passage directly alludes to 2 Corinthians 4:17, using similar wording and the core concept of light affliction leading to eternal glory.
With Jesus at our head we all descended from the city down to this earth, on a great and mighty mountain, which could not bear Jesus up, and it parted asunder, and there was a mighty plain. Then we looked up and saw the great city, with twelve foundations, and twelve gates, three on each side, and an angel at each gate. We all cried out, “The city, the great city, it's coming, it's coming down from God out of heaven,” and it came and settled on the place where we stood. Then we began to look at the glorious things outside of the city. There I saw most glorious houses, that had the appearance of silver, supported by four pillars set with pearls most glorious to behold. These were to be inhabited by the saints. In each was a golden shelf. I saw many of the saints go into the houses, take off their glittering crowns and lay them on the shelf, then go out into the field by the houses to do something with the earth; not as we have to do with the earth here; no, no. A glorious light shone al…
"And I John saw the holy city, new Jerusalem, coming down from God out of heaven, prepared as a bride adorned for her husband."
Both passages describe the New Jerusalem descending from heaven. EGW expands on the description, but the core image is clearly derived from Revelation 21:2.