Genesis 39:2

The Lord was with Joseph. Though Joseph found himself in a foreign land, abased from the position of favored son in a wealthy home to the social status of a slave, Jehovah was still at his side to bless and to prosper the work of his hands. It is God’s design that men of the world, attracted by the diligence, care, and energy manifested by his faithful servants on earth, shall thereby learn to Him. Potiphar’s confidence in Joseph increased, as he observed the blessings of Joseph’s God upon his property in the house and in the field, with the result that he eventually left to him the management of all his personal affairs.

Obviously, Joseph was attentive, diligent, and conscientious in the performance of his household duties, as well as faithful and devoted to the interests of his master. Success seldom comes to the negligent, the idle, or the unprincipled. Though he was conscious that Jehovah was watching him (v. 9; ch. 45:5), it must have been a source of satisfaction to Joseph to know that his faithful service was appreciated by his earthly master.