Alcuin of York — on Rev 12:11 (COMMENTARY ON REVELATION)

“And they overcame him by the blood of the Lamb, and by the word of their testimony. They overcome him by the blood of the Lamb because they follow the example of the sufferings of Christ, and by the word of their testimony because they keep the rightness of faith. It is then added concerning them, and they loved not their lives unto death, which means that they put themselves to death so as not to love their lives wickedly.”