Isaac and Abimelech
A famine came upon the land where Isaac and his family lived -- in Gerar under King Abimelach. God asked Isaac to stay despite the famine. Isaac and his people were successful in digging up wells and their herds grew. Isaac did as his father Abraham had done -- he pretended his wife Rebekah was his sister. Abililech discovered the lie and orderd on one to hurt Isaac or his people.
But Abimilech's people were not happy about Isaac's successful wells so the plugged them up. Soon Isaac moved further into the valley, away from these people. Again, he was successful and his herds and wealth grew. Isaac wasn't looking for a fight however. He just kept moving until he found, not only water, but peace.
Now Abimelech saw the need to arrange a treaty with Isaac so they would not attack each other. Isaac's enemies also realized (i.e. were given to realize) that they should make peace with Isaac ("We saw certainly that the LORD was with thee"), a lesson that applies to anyone who genuinely obeys the LORD. When a nation truly obeys the LORD, rather than arrogantly claiming to be the LORD's people on their own rebellious "it's right if we say it is" terms, their borders and their people will always be safe and secure.
Isaac built an altar to God and was faithful. When Esau was 40 years old he married Judith, a Hittite, and also married Basemate. They were a source of grief to Isaac and Rebekah.
A pattern has emerged through Genesis where humans place great value on "first-borns" but God puts more value on "second-borns" who seem to have learned from life to be less arrogant and more moral.