Isaiah 65:18

“But be you glad, and rejoice for ever in that which I create, &c.] This may refer either to persons converted, both at the beginning of the Gospel, and in the latter day, whether Jews or Gentiles; who are the Lord’s creation, or new creatures, being made new men; having new hearts and spirits given them, or created within them; new principles of life, light, grace, and holiness, wrought in them, which are the produce of almighty and creating power; and all such instances are matter of joy, as to the angels in heaven, so to the saints on earth, and especially to the ministers of the Gospel; because of the grace bestowed on men, the glory brought to God, and their own ministry blessed and…”

“rejoice for ever . . . Jerusalem-- (Isa 51:11). "Everlasting joy . . . Zion." Spiritually (Th1 5:16).”

“But be ye glad and rejoice - (See the notes at Isaiah 51:11). Forever - It is not to be momentary happiness - like a bright morning that is soon overcast with clouds. The joy of God’s people is to endure for ever, and they shall have ceaseless cause of praise and thanksgiving. I create Jerusalem a rejoicing - A source of rejoicing; or a place of rejoicing. And her people a joy - That is, in themselves joyful, and a source of joy to all others. The idea is, that the church would be a place of the highest happiness, and that they who were redeemed would have occasion of perpetual joy. The Saviour did not come to minister gloom, nor is the true effect of religion to make his people melancholy.…”

“You - The church, as well under the gospel, as under the law. Isaiah 65:20”

“65:18-19 Jerusalem here symbolizes God’s eternal kingdom (Rev 21:1-4).”

“Isa 12:4-6, Isa 42:10-12, Isa 44:23, Isa 49:13, Isa 51:11, Isa 52:7-10, Isa 66:10-14; Psa 67:3-5; Psa 96:10-13, Psa 98:1-9; Zep 3:14; Zac 9:9; Th1 5:16; Rev 11:15-18; Rev 19:1-6 Isaiah 65:19”