Revelation 14:2-3

2And I heard a voice out of the heaven as a voice of many waters, and as a voice of great thunder. And the voice which I heard [was] as of harp-singers harping with their harps;

3and they sing a new song before the throne, and before the four living creatures and the elders. And no one could learn that song save the hundred [and] forty-four thousand who were bought from the earth.