Genesis 21 focuses on three key events in Abraham's life: the birth of Isaac, the banishment of Hagar and Ishmael, and the covenant with Abimelech.
The Birth of Isaac: As God promised, Sarah gave birth to Abraham's son Isaac when Abraham was 100 years old. Isaac's name means "laughter," reflecting Sarah's joy and initial disbelief that she would bear a child in her old age. Abraham circumcised Isaac on the eighth day as commanded by God.
Hagar and Ishmael's Banishment: After Isaac was weaned, Sarah saw Ishmael (Abraham's firstborn son by Hagar) mocking Isaac. Sarah demanded that Abraham send Hagar and Ishmael away. Though upset, Abraham obeyed after God reassured him that Ishmael would also become a nation. Hagar and Ishmael nearly died in the wilderness until God provided water and promised that Ishmael would become a great nation. Ishmael grew up in the wilderness of Paran and became an archer.
The Covenant with Abimelech: Abimelech, king of Gerar, recognized God's favor on Abraham and proposed a treaty of peace between them. Abraham agreed but raised an issue about a well that Abimelech's servants had seized. They resolved the dispute, and Abraham planted a grove at Beersheba ("well of the sevenfold oath") to commemorate their covenant. Abraham continued to stay in Philistine territory.
