'Life guard' in the Bible

And the Midianites sold him into Egypt, to Potiphar, a chamberlain of Pharaoh, the captain of the life-guard.

And Joseph was brought down to Egypt; and Potiphar, a chamberlain of Pharaoh, the captain of the life-guard, an Egyptian, bought him of the hand of the Ishmaelites who had brought him down thither.

and he put them in custody into the house of the captain of the life-guard, into the tower-house, into the place where Joseph was imprisoned.

And the captain of the life-guard appointed Joseph to them, that he should attend on them. And they were several days in custody.

And there was there with us a Hebrew youth, a bondman of the captain of the life-guard, to whom we told them, and he interpreted to us our dreams; to each he interpreted according to his dream.