The opening of the seventh seal ends the first act and starts a dramatic silence. This silence suggests the mystery of God's actions in the world (Revelation 10:4; 1 Kings 19:11–12). This mysterious silence may be similar to God's rest on the seventh day of creation (Genesis 2:1–3; see also Hebrews 4:1–11).
half an hour: This short pause comes before the second act of divine judgment, when God will answer his people's prayers.