Then I saw the Lamb standing on Mount Zion, and with him were 144,000 who had his name and his Father's name written on their foreheads.
And I heard a sound from heaven like the roaring of a great waterfall or the rolling of mighty thunder. It was like the sound of many harpists playing together.
This great choir sang a wonderful new song in front of the throne of God and before the four living beings and the twenty-four elders. And no one could learn this song except those 144,000 who had been redeemed from the earth.
For they are spiritually undefiled, pure as virgins, following the Lamb wherever he goes. They have been purchased from among the people on the earth as a special offering to God and to the Lamb.
References for Revelation 14:4
No falsehood can be charged against them; they are blameless.