The 7th seal causes silence in heaven for about half an hour. The prayers of the saints ascend to God, and 7 angels with trumpets prepare to sound.
And when he had opened the seventh seal, there was silence in heaven about the space of half an hour. And I saw the seven angels which stood before God; and to them were given seven trumpets. And another angel came and stood at the altar, having a golden censer; and there was given unto him much incense, that he should offer [it] with the prayers of all saints upon the golden altar which was before the throne. And the smoke of the incense, [which came] with the prayers of the saints, ascended up before God out of the angel’s hand. And the angel took the censer, and filled it with fire of the altar, and cast [it] into the earth: and there were voices, and thunderings, and lightnings, and an earthquake. And the seven angels which had the seven trumpets prepared themselves to sound. (Revelation 8:1-6)