Revelation 6:9

6:9 Now when the Lamb opened the fifth seal, I saw under the altar the souls of those who had been violently killed because of the word of God and because of the testimony they had given.

Revelation 12:11

12:11 But they overcame him

by the blood of the Lamb

and by the word of their testimony,

and they did not love their lives so much that they were afraid to die.