Revelation 7 — the pause before the trumpets
Revelation 6 closes with the sixth seal: cosmic disruption, the kings of the earth hiding in caves, "the great day of his wrath is come." Revelation 8 will open with the seventh seal and the seven trumpet judgments. Between them, John sees an interruption. Four angels stand at the four corners of the earth, holding the four winds. A fifth angel rises from the east "having the seal of the living God," and cries:
"Hurt not the earth, neither the sea, nor the trees, till we have sealed the servants of our God in their foreheads." (Rev 7:3)
The Greek for seal is sphragis (noun) and sphragizō (verb) — the impressed mark of a signet, the certifying stamp of ownership. It is the same word used in Roman commerce for the seal on a wax tablet, in Roman law for the seal on a will, and in Roman religion for the brand on a slave. To be sealed is to be owned, certified, and protected.
The number sealed is 144,000 — twelve thousand from each tribe of Israel (Rev 7:4–8). The literal/symbolic question (a literal Jewish remnant? the totality of the church under tribal symbolism?) is debated and the page does not adjudicate; what is structurally undeniable is that the sealing happens before the trumpets blow. The mark is given, then the destroyer comes. The Ezekiel pattern.
Two chapters later, Rev 9:4 confirms the protective function. The locust plague is told not to hurt vegetation, "but only those men which have not the seal of God in their foreheads." The seal is the criterion. The unmarked are the targets.
Revelation 14 — what the mark says
Five chapters after the sealing, the same 144,000 appear on Mount Zion with the Lamb. They are now identified more precisely:
"And I looked, and, lo, a Lamb stood on the mount Sion, and with him an hundred forty and four thousand, having his Father's name written in their foreheads." (Rev 14:1)
In Ezekiel the mark was taw (the letter that means "mark"). In Rev 7 it is the seal of the living God (an unspecified imprint of ownership). By Rev 14 it is the Father's name. The progression is: from a sign that means "marked" → to a seal that means "owned" → to a name that means "his."
The counter-image is unavoidable. Revelation 13:16 — the second beast "causeth all, both small and great, rich and poor, free and bond, to receive a mark in their right hand, or in their foreheads." Two marks; two ownerships; the same surface (forehead) and an additional surface (right hand, the active hand). Revelation insists on the question: whose mark do you bear.
Revelation 22 — the final naming
The book closes with the same forehead one last time:
"And there shall be no night there; and they need no candle, neither light of the sun; for the Lord God giveth them light: and they shall reign for ever and ever. Blessed are they that do his commandments, that they may have right to the tree of life, and may enter in through the gates into the city. ... And they shall see his face; and his name shall be in their foreheads." (Rev 22:4–5, with 14)
The work of marking is finished. The marked see the face of the one whose name they bear. The mark has matured from rescue to relationship.
Paul's bridge — the church's present seal
Between Ezekiel and Revelation, Paul tells the church that the sealing the prophet saw and the apostle will see is now. Ephesians 1:13: at belief, the believer is sealed with the Holy Spirit of promise. Ephesians 4:30: that seal lasts unto the day of redemption. The Greek verb is identical to John's sphragizō. The Spirit is the seal. The forehead Ezekiel marked, John foresees, and Paul confirms is the church's present possession.