Matthew Henry Commentary Revelation 7:1-8

"After his I saw four angels standing at the four corners of the earth, holding the four winds of the earth, that no wind should blow on the earth, or on the sea, or upon any tree. And I saw another angel ascend from the sunrising, having the seal of the living God: and he cried with a great voice to the four angels to whom it was given to hurt the earth and the sea, saying, Hurt not the earth, neither the sea, nor the trees, till we shall have sealed the servants of our God on their foreheads. And I heard the number of them that were sealed, a hundred and forty and four thousand, sealed out of every tribe of the children of Israel: Of the tribe of Judah [were] sealed twelve thousand: Of the tribe of Reuben twelve thousand; Of the tribe of Gad twelve thousand; Of the tribe of Asher twelve thousand; Of the tribe of Naphtali twelve thousand; Of the tribe of Manasseh twelve thousand; Of the tribe of Simeon twelve thousand; Of the tribe of Levi twelve thousand; Of the tribe of Issachar twelve thousand; Of the tribe of Zebulun twelve thousand; Of the tribe of Joseph twelve thousand; Of the tribe of Benjamin [were] sealed twelve thousand." — Revelation 7:1-8 (ASV)

In the figurative language of Scripture, the blowing of the four winds together means a dreadful and general destruction. But the destruction is delayed. Seals were used to mark for each person his own possessions. This mark is the witness of the Holy Spirit, imprinted in the hearts of believers.

And the Lord would not allow his people to be afflicted before they were marked, so that they might be prepared against all conflicts. And observe, concerning those who are so sealed by the Spirit, the seal must be on the forehead, clearly visible to friends and foes alike, but not by the believer himself, except as he looks steadfastly in the mirror of God's word.

The number of those who were sealed may be understood to represent the remnant of people whom God reserved. Though the church of God is only a small flock in comparison with the wicked world, yet it is a truly large society and is to be further enlarged. Here the universal church is represented by the type of Israel.