C. F. Keil and Franz Delitzsch on Genesis 39:21-23

Gen 39:21-23

In the prison itself Jehovah was with Joseph, procuring him favour in the eyes of the governor of the prison, so that he entrusted all the prisoners to his care, leaving everything that they had to do, to be done through him, and not troubling himself about anything that was in his hand, i.e., was committed to him, because Jehovah made all that he did to prosper. “The keeper” was the governor of the prison, or superintendent of the gaolers, and was under Potiphar, the captain of the trabantes and chief of the executioners (Gen 37:36).