The angel throwing fire down to earth marks the dramatic start of God's judgment (see Genesis 19:24; Exodus 9:23; Leviticus 10:2; Deuteronomy 9:3; 2 Kings 1:10).
thunder, lightning … earthquake: These disasters remind us of God's power, presence, and judgment (also Revelation 11:19; 16:18; see Exodus 19:18–19; 1 Kings 19:11–12; Isaiah 29:6).