One of the earliest examples of the taking of an oath by God is in the remarkable story of the execution of His covenant with Abraham. When God had called Abraham out of Ur of the Chaldees into Palestine He promised that the land would be his and would belong to his seed forever. Abraham had believed God implicitly, for God is the only being in the universe who cannot lie and who has never made a mistake.

This is the fourth of Christ's six great illustrations of true morality in the Sermon on the Mount: victory over anger, purity in sexual matters, faithfulness in marriage, truth, selflessness, and love. It teaches the paramount importance of speaking truthfully. 

"Christ is the faithful one. We are the ones who slip into flirtation and then into adultery with the world. We are loved by Christ Jesus, but we are drawn aside by our own desires and seduced from our love of Christ. Such a seduction is the worst of all transgressions since it is the sin against the love of Christ. He is faithful to the end, loving us when we were unlovely, and taking us through all steps of our wandering to the place of redemption and final attachment to Himself forever. 

"Hosea did not act in this way because he was reflecting the love of God, and God never acts thus with those whom He has redeemed by His blood. Hosea took Gomer and led her toward their home, and as they went he said to her, 'Thou shalt abide for me many days; thou shalt not play the harlot, and thou shalt not be for another man: so will I also be for thee.' 

"Does God love us like that? Listen to the story as it is recorded in the third chapter of Hosea: 'Then said the LORD unto me, Go yet, love this woman, beloved of her friend, this adulteress, according to the love of the LORD toward the children of Israel.' Love her? 'Even as the LORD loves the people of Israel.' But Lord, she is a harlot, sold on the auction block as an adulterous slave! 'Go love her,' says God, 'love her, even as the Lord loves you.'