'Themselves' in the Bible

"I know your works, and your toil and perseverance, and that you can't tolerate evil men, and have tested those who call themselves apostles, and they are not, and found them false.

The kings of the earth, the princes, the commanding officers, the rich, the strong, and every slave and free person, hid themselves in the caves and in the rocks of the mountains.

The seven angels who had the seven trumpets prepared themselves to sound.