Poole on Revelation 7:17: The Blessedness of Heaven, Part 2
Verse 17: For the Lamb which is in the midst of the throne (Ps. 23:1; 36:8; John 10:11, 14) shall feed them, and shall lead them unto living fountains of waters: (Is. 25:8; Rev. 21:4) and God shall wipe away all tears from their eyes.
[The Lamb, etc.] Christ, σύνθρονος, enthroned with, the Father (see Revelation 5:6 [Grotius, Menochius]) shall feed them (Cluverus), with heavenly Manna (Tirinus), with the sight of His face (Cotterius, similarly Pareus), Psalm 16:11 (Pareus), and will supply them with all good things (Durham).
For the Lamb which is in the midst of the throne; Christ, the Lamb mentioned Revelation 5:6.
[He shall lead them to, etc., ἐπὶ ζώσας, etc.] To living (that is, bubbling and springing [Piscator], or perpetual [Grotius, similarly Camerarius, Durham]) fountains of waters (Beza, Piscator). The Latin reads ἐπὶ ζωῆς πηγὰς, etc., to the fountains of life, etc. There is then a Trajection in the place of πηγὰς ὑδάτων ζωῆς, fountains of waters of life. Ὕδατα ζωῆς, waters of life, after the fashion of the Hebrews, in the place of ὕδατα ζῶντα, living waters, as Virgil says. For indeed it is very sweet to quench thirst by a stream of dancing water; therefore, every comfort, and everything which refreshes us, is expressed by this image. See Psalm 23:2; 36:8; 42:1. And to this Christ alludes, John 4:10, 11, 14; 7:38. In Isaiah, in the place of these words, you have, For the One pitying them shall rule them, and He shall carry them to fountains of waters (Grotius). Nothing is more agreeable or salutary to travelers, at least in those hot places, than fountains of waters, etc. By which here he understands divine, efficacious, and eternal refreshments springing up unto eternal life, John 4:14 (Cluverus).
[And He shall wipe away, etc.] As a parent in a coaxing manner soothes crying children, etc. (Menochius, similarly Pareus): that is to say, He will fully console them (Menochius). Cicero also said, to wipe away grief, mourning, sorrow, by a figure derived from Tears. The same expression is used in Revelation 21:4. In the Greek of Isaiah 25:8, it is ἀφεῖλε, He takes away, etc. But it is somewhat more to wipe away, than, what is there, to take away (Grotius).
Shall feed them, etc.; shall take care of them, to satisfy and to protect them, and give them the best supplies, and both make them to forget their former sorrows, and prevent any further cause of sorrow and affliction to them. A perfect description of the glorious and happy state of saints in heaven. For wherein lieth the happiness of heaven, but in a freedom from all the evils that encumber us in this life, and the enjoyment of all the happiness we are capable of, and being ever with the Lord Jesus Christ, under his influence and conduct? So as I cannot agree with Mr. Mede, or any of those who think this vision and these phrases describe any happy, peaceable state of the church in this life, after the throwing down of antichrist; but do think that John was showed this great reward of martyrs, to encourage the church of God under all those evils they were to suffer under antichrist and the beast, in that period of time which is described mystically upon the opening of the seventh seal, which we now come to in the next chapter.
 Greek: ὅτι τὸ ἀρνίον τὸ ἀνὰ μέσον τοῦ θρόνου ποιμανεῖ αὐτούς, καὶ ὁδηγήσει αὐτοὺς ἐπὶ ζώσας πηγὰς ὑδάτων, καὶ ἐξαλείψει ὁ Θεὸς πᾶν δάκρυον ἀπὸ τῶν ὀφθαλμῶν αὐτῶν.  Latin: ad vitæ fontes aquarum. Eclogue 5:47.  Isaiah 49:10.