Revelation 13:16-18: And the second beast required all people small and great, rich and poor, free and slave, to receive a mark on their right hand or on their forehead, so that no one could buy or sell unless he had the mark—the name of the beast or the number of its name.
14:9-11: And a third angel followed them, calling out in a loud voice, “If anyone worships the beast and its image, and receives its mark on his forehead or on his hand, he too will drink the wine of God’s anger, poured undiluted into the cup of His wrath. And he will be tormented in fire and sulfur in the presence of the holy angels and of the Lamb. And the smoke of their torment rises forever and ever. Day and night there is no rest for those who worship the beast and its image, or for anyone who receives the mark of its name.”
Revelation 16:2: So the first angel went and poured out his bowl on the earth, and loathsome, malignant sores broke out on those who had the mark of the beast and worshiped its image.
14:13:Then I looked and saw the Lamb standing on Mount Zion, and with Him 144,000 who had His name and His Father’s name written on their foreheads. And I heard a sound from heaven like the roar of many waters and the loud rumbling of thunder. And the sound I heard was like harpists strumming their harps.