“I am God Almighty,” said Jehovah to Abram (Abraham) almost 4,000 years ago.a “Walk before me and prove yourself faultless. And I will give my covenant between me and you, that I may multiply you very, very much.” When Abraham was 99 years old and his barren wife Sarah 10 years younger, Jehovah predicted that Abraham would become the father of “a crowd of nations.” (Genesis 17:1-4) Being almighty​—omnipotent—​Jehovah used his power to overcome any obstacle that could block fulfillment of his promise to Abraham, enabling that patriarch to become the father of Isaac. In time, Abraham did, indeed, become the progenitor of the Israelites and others.​—Genesis 21:1-3; 25:1-4.