Revelation 7:2

And I saw another angel
Not Constantine, who came from the eastern parts to the empire, with the true knowledge of God, and the authority of God to propagate it; and who repressed the four angels, or evil spirits, contention, ambition, heresy, and war, from doing the mischief they otherwise would; and sealed the saints, by giving them a platform of doctrine at the council of Nice, as Brightman and others think. But the uncreated angel, the angel of the covenant, the Lord Jesus Christ; for who but he should have the privy seal of heaven, who is the angel of the great council, as the Septuagint render ( Isaiah 9:6 ) and who could speak in such an authoritative manner to the four angels, "saying, hurt not the earth" but he who is the head of all principality and power? and who should seal the servants of the Lord, but he who has them in his hands, and keeps them by his power, so that none of them shall perish? And to him agrees all that follows:

ascending from the east;
from Judea, from Zion, from whence Christ, as the salvation, or Saviour of Israel, came, ( Psalms 14:7 ) ; and whose name is the east, as some render ( Zechariah 3:8 ) ; he is the dayspring from on high, the sun of righteousness, who rose from the east, the place of the rising sun, and brought light, life, and joy to his people, when he came to seal them. Compare with this ( Ezekiel 43:1 Ezekiel 43:2 Ezekiel 43:4 ) ( 44:1-4 ) ( Ezekiel 46:1 Ezekiel 46:2 ) ( Ezekiel 47:1 ) .

Having the seal of the living God;
having the impress of deity upon him, being the brightness of his Father's glory, and the express image or character of his person; having a testimony, an authentic proof and demonstration of his being the Son of God, of his being the true and living God; as also a commission from God, as Mediator, being sealed by him; and having all power and authority from him, to seal and secure the people which were given unto him, and for which purpose he now came: to which may be added, that Christ has the Spirit, with his gifts and graces, without measure, by which the saints are sealed unto the day of redemption; and moreover has likewise the seal of the book of life, or of eternal election, in his hands; the elect are chosen in him, and the book of life, in which their names are written to eternal life, is in his keeping, and is therefore called the Lamb's book of life. The Jews speak ^F1 of the east gate of one of the palaces they suppose above, which they say is shut all the six days, and on the sabbath day is opened, and the governor of this palace has two ministers, one on his right hand, and one on his left, and two seals in their hands, (Myyx Mtwx) , "the seal of life", and the seal of death, and all the books of the world, before them; an, some are sealed to life, and some to death, with which this passage may be compared. They speak also of an angel that presides at the eastern part of the heavens, who receives the prayers of the Israelites, whose name they call "Gazardia" ^F2, as this same angel is said to offer up the prayers of the saints, ( Revelation 8:3 ) .

And he cried with a loud voice to the four angels;
to show his power and authority over them, they being his creatures and ministers; and to express his great concern for his people, his care of them, and affection for them; and to signify the danger they were in through the calamities that were coming on, should they not be sealed:

to whom it was given to hurt the earth and the sea:
they had a commission from God to let loose the winds, or to bring on wars, devastations, calamities, and plagues, of various sorts, upon the Roman empire, now Christian; and on the seat of the beast, not only on the continent, but upon the islands also, even upon all the nations, tongues, and people subject to the see of Rome.