Revelation 5:6

5:6 Then I saw standing in the middle of the throne and of the four living creatures, and in the middle of the elders, a Lamb that appeared to have been killed. He had seven horns and seven eyes, which are the seven spirits of God sent out into all the earth.

Revelation 5:9

5:9 They were singing a new song:

“You are worthy to take the scroll

and to open its seals

because you were killed,

and at the cost of your own blood you have purchased for God

persons from every tribe, language, people, and nation.