45 And Pharaoh called Joseph’s name Zaphnath-Paaneah. And he gave him as a wife Asenath, the daughter of Poti-Pherah priest of On. So Joseph went out over all the land of Egypt.
46 Joseph was thirty years old when he stood before Pharaoh king of Egypt. And Joseph went out from the presence of Pharaoh, and went throughout all the land of Egypt.
47 Now in the seven plentiful years the ground brought forth abundantly.
48 So he gathered up all the food of the seven years which were in the land of Egypt, and laid up the food in the cities; he laid up in every city the food of the fields which surrounded them.
49 Joseph gathered very much grain, as the sand of the sea, until he stopped counting, for it was immeasurable.
50 And to Joseph were born two sons before the years of famine came, whom Asenath, the daughter of Poti-Pherah priest of On, bore to him.
51 Joseph called the name of the firstborn Manasseh: “For God has made me forget all my toil and all my father’s house.”
52 And the name of the second he called Ephraim: “For God has caused me to be fruitful in the land of my affliction.”
53 Then the seven years of plenty which were in the land of Egypt ended,
54 and the seven years of famine began to come, as Joseph had said. The famine was in all lands, but in all the land of Egypt there was bread.
55 So when all the land of Egypt was famished, the people cried to Pharaoh for bread. Then Pharaoh said to all the Egyptians, “Go to Joseph; whatever he says to you, do.”
56 The famine was over all the face of the earth, and Joseph opened all the storehouses and sold to the Egyptians. And the famine became severe in the land of Egypt.
57 So all countries came to Joseph in Egypt to buy grain, because the famine was severe in all lands.
[Pharaoh] gave Joseph an Egyptian name, Zaphnath-paaneah, the exact meaning of which is somewhat doubtful. It has been variously interpreted as “Abundance of life,” “Savior of the World,” “Revealer of Secrets,” “God’s Word Speaking Life,” “Furnisher of Sustenance,” and so on. This variety of possible names at least indicates that Pharaoh probably conferred a name on him which was expressive of his unique contributions to Egypt at this time in her history.
Pharaoh next obtained a suitable wife for Joseph … The girl chosen was the daughter of an Egyptian priest. Nothing is said about her except her name and parentage. We can only assume that Joseph, dedicated as he was to the Lord, would not have consented to marry her unless he was satisfied that she would leave her own pagan beliefs to follow Jehovah. …
The girl’s name was Asenath, which apparently indicates something like “Dedicated to Neith,” Neigh being the Egyptian equivalent of the goddess Minerva. Thus there is little doubt that she had been brought up in the polytheistic Egyptian religion. Her father, Potipherah (meaning essentially the same thing as Potiphar, “given by Ra, the sun-god”), was actually a prominent priest in this religious system, located at the temple at On (probably the same as Heliopolis, a city specially devoted to the sun-god). … So far as the record goes, at least, Joseph never married any wife other than Asenath. — Morris, pages 587-588.
Joseph was 30 years old when he interpreted Pharaoh’s dream, which means that he had been away from his family for 13 years.
It was during the seven-year period of prosperity that two sons were born to Joseph and Asenath. These two sons were destined to give their names to two of the most prominent tribes of Israel.
The boys were named by Joseph in recognition of his unusual experiences. The first was named Manasseh, meaning, “Forgetting,” and signifying that God had caused Joseph to forget all the long years of suffering and rejection he had endured. …
His second son was named Ephraim (“Doubly Fruitful”) in thankfulness for the manner in which God had so richly blessed him and prospered him. — Morris, page 589
God caused the crops of Egypt to grow so abundantly that just 20% of the crop from the seven good years was enough to supply the needs of the Egyptians and the surrounding nations during the seven years of famine. Notice that Joseph didn’t just give away the grain, but sold it—perhaps to replenish the treasury for the cost of buying the grain to begin with.