Revelation 11:15 → Isaiah 9:7

In its original horizon Isaiah 9:7 announces the eternal Davidic throne: "Of the increase of His government and peace there will be no end. He will reign on the throne of David and over his kingdom... from that time and forevermore." The Hebrew lemarbēh ham-miśrāh... ʾēn-qēṣ ("of the increase of the government... no end") and mēʿattāh wəʿaḏ-ʿôlām ("from now and forevermore") re-affirm the 2 Samuel 7 eternal-throne clause, now lodged in the specific child born and son given (9:6) — the promise's divine guarantee being "the zeal of the LORD of Hosts." At the seventh trumpet, heaven's loud voices declare the consummation of that promise: "The kingdom of the world has become the kingdom of our Lord and of His Christ, and He will reign forever and ever" — kai basileusei eis tous aiōnas tōn aiōnōn. John's "He will reign forever and ever" answers Isaiah's "no end... forevermore," the announced Davidic government arriving at its unending fullness. The link is best classified an Echo: there is no quotation and no determinable Vorlage (the closer formal source for Revelation's "kingdom" diction is the Danielic everlasting-dominion language of Dan 2:44 and 7:14, already documented), but the eternal-reign cadence of Isa 9:7 sounds unmistakably through the trumpet acclamation. The road to Christ runs by Promise-Fulfillment along the Kingdom longitudinal theme, not typology (anti-default): Isaiah 9:7 is itself a prophecy of an everlasting reign, not a historical type with an analogical figure awaiting escalation — so Christ does not antitypically correspond to it; He fulfills the announced promise. And the telos is not a chart closed but a King beheld: the unbreakable, never-ending reign of the Lamb is the believer's deepest safety and gladness — a throne no rival kingdom can topple and no death can end — so that "He will reign forever and ever" is heard not as cold inevitability but as the sweetest of all good news, the everlasting Prince of Peace seen, and seen, savored.