A.T. Robertson Commentary Revelation 22:1

"And he showed me a river of water of life, bright as crystal, proceeding out of the throne of God and of the Lamb," — Revelation 22:1 (ASV)

He shewed me (εδειξεν μο). The angel as in 21:9,10 (cf. 1:1; 4:1). Now the interior of the city.

A river of water of life (ποταμον υδατος ζωης). For υδωρ ζωης (water of life) see 7:17; 21:6; 22:17; John 4:14. There was a river in the Garden of Eden (Genesis 2:10). The metaphor of river reappears in Zec 14:8; Ezekiel 47:9, and the fountain of life in Joe 3:18; Jeremiah 2:13; Proverbs 10:11; 13:14; 14:27; 16:22; Psalms 36:10.

Bright as crystal (λαμπρον ως κρυσταλλον). See 4:6 for κρυσταλλον and 15:6; 19:8; 22:16 for λαμπρον. "Sparkling like rock crystal" (Swete), shimmering like mountain water over the rocks.

Proceeding out of the throne of God and of the Lamb (εκπορευομενον εκ του θρονου του θεου κα του αρνιου). Cf. Ezekiel 47:1; Zechariah 14:8. Already in 3:21 Christ is pictured as sharing the Father's throne as in Heb 1:3. See also 22:3. This phrase has no bearing on the doctrine of the Procession of the Holy Spirit.