There was very little food in the land. The same thing had been true earlier, in Abraham's time. Isaac went to Abimelech in Gerar. Abimelech was the king of the Philistines.
References for Genesis 26:1
The LORD appeared to Isaac. He said, "Do not go down to Egypt. Live in the land where I tell you to live.
Stay here for a while. I will be with you and give you my blessing. I will give all of these lands to you and your children after you. And I will keep the promise I made with an oath to your father Abraham.
I will make your children after you as many as the stars in the sky. And I will give them all these lands. All nations on earth will be blessed because of your children.
"I will do all of those things because Abraham obeyed me. He did what I required. He kept my commands, my rules and my laws."
So Isaac stayed in Gerar.
The men of that place asked him about his wife. He said, "She's my sister." He was afraid to say, "She's my wife." He thought, "The men of this place might kill me because of Rebekah. She's a beautiful woman."
Isaac had been there a long time. One day Abimelech, the king of the Philistines, looked down from a window. He saw Isaac hugging and kissing his wife Rebekah.
So Abimelech sent for Isaac. He said, "She's really your wife, isn't she? Why did you say, 'She's my sister'?" Isaac answered him, "I thought I might lose my life because of her."
Then Abimelech said, "What have you done to us? What if one of the men had sex with your wife? Then you would have made us guilty."
So Abimelech gave orders to all of the people. He said, "You can be sure that anyone who harms this man or his wife will be put to death."
Isaac planted crops in that land. That same year he gathered 100 times more than he planted. That was because the LORD blessed him.
Isaac became rich. His wealth continued to grow until he became very rich.
He had many flocks and herds and servants. Isaac had so much that the Philistines became jealous of him.
So they stopped up all of the wells the servants of his father Abraham had dug. They filled them with dirt.
Then Abimelech said to Isaac, "Move away from us. You have become too powerful for us."
So Isaac moved away from there. He camped in the Valley of Gerar and settled there.
Isaac opened up the wells again. They had been dug in the time of his father Abraham. The Philistines had stopped them up after Abraham died. Isaac gave the wells the same names his father had given them.
Isaac's servants dug for wells in the valley. There they discovered a well of fresh water.
But the people of Gerar who took care of their herds argued with the people who took care of Isaac's herds. "The water is ours!" the people of Gerar said. So Isaac named the well Esek. That's because they argued with him.
Then Isaac's servants dug another well. They argued about that one too. So he named it Sitnah.
He moved on from there and dug another well. But no one argued about that one. So he named it Rehoboth. He said, "Now the LORD has given us room. Now we will do well in the land."
From there Isaac went up to Beersheba.
That night the LORD appeared to him. He said, "I am the God of your father Abraham. Do not be afraid. I am with you. I will bless you. I will increase the number of your children because of my servant Abraham."
Isaac built an altar there and worshiped the Lord. There he set up his tent. And there his servants dug a well.
During that time, Abimelech had come to him from Gerar. Ahuzzath had come with him. So had Phicol, Abimelech's army commander. Ahuzzath was Abimelech's personal adviser.
Isaac asked them, "Why have you come to me? You were angry with me and sent me away."
They answered, "We saw clearly that the LORD was with you. So we said, 'We should make an agreement by taking an oath.' The agreement should be between us and you. We want to make a peace treaty with you.
Promise that you won't harm us. We didn't harm you. We always treated you well. We sent you away in peace. Now the LORD has blessed you."
Then Isaac had a big dinner prepared for them. They ate and drank.
Early the next morning the men made an agreement with an oath. Then Isaac sent the men of Gerar on their way. And they left in peace.
That day Isaac's servants came to him. They told him about the well they had dug. They said, "We've found water!"
So he named it Shibah. To this day the name of the town has been Beersheba.
When Esau was 40 years old, he got married to Judith. She was the daughter of Beeri the Hittite. He also married Basemath. She was the daughter of Elon the Hittite.
Isaac and Rebekah became very upset because Esau had married Hittite women.