7:2 I saw another angel coming from the east with the seal of the living God. He cried out in a loud voice to the four angels who had been allowed to harm the land and sea,
I saw another angel coming from the east with the seal of the living God.
This fifth angel (some commentaries indicate this may possibly even be Christ himself) ascends from the east (possibly Jerusalem) or may refer to Jesus description of His second coming (Matthew 24:23-27).
The SEAL of THE LIVING GOD is a special identifying mark given to BOND-SERVANTS (see next verse).
He cried out in a loud voice to the four angels who had been allowed to harm the land and sea,
The voice was loud enough to reach around the earth. Note that the present church age "Sealer" is the Holy Spirit (2 Corinthians 1:20-22, Ephesians 1:13-14, Ephesians 4:30).
To 'not harm' a particular group took place before. The Egyptians were plagued (Exodus 9:1-7, Exodus 9:22-26, Exodus 10:21-23, and Exodus 11:4-7) while the Israelites had a distinctive mark of protection.