Revelation 5:5, 8-9

and one of the elders saith unto me, Weep not; behold, the Lion that is of the tribe of Judah, the Root of David, hath overcome to open the book and the seven seals thereof.

And when he had taken the book, the four living creatures and the four and twenty elders fell down before the Lamb, having each one a harp, and golden bowls full of incense, which are the prayers of the saints. And they sing a new song, saying, Worthy art thou to take the book, and to open the seals thereof: for thou wast slain, and didst purchase unto God with thy blood men of every tribe, and tongue, and people, and nation