What is the biblical account of Isaac?

from the old testament

• Prior to Isaac’s birth, God changed Abram’s name and established a covenant with him. God promised that Abraham's wife Sarah would bear Abraham's heir in a year's time. When Abraham laughed at the thought of him at one hundred fathering a child and Sarah at age ninety giving birth, God named their son Isaac, or "laughter." God also told Abraham that Ishmael was not the son of promise (Genesis 17—18).
• Isaac was born when Abraham was one hundred years old and Sarah ninety, as they had been told, (Genesis 21).
• When God called Abraham to sacrifice Isaac (Genesis 22), Isaac followed his father, carried the wood, and trusted God, who provided a ram instead.
• After Sarah died, Abraham sent his servant to his family's home in Haran to find Isaac a wife. Rebekah agreed to return with him and marry Isaac. Isaac fell in love and was comforted after Sarah's death (Genesis 24).
• When Abraham died (Genesis 25:1–11), Isaac and Ishmael buried him together with no sign of animosity. Abraham was buried in the same cave Sarah had been buried.
• Like Sarah, Rebekah was barren. Isaac prayed for her, and when he was sixty years old she became pregnant with twins. When she asked God why they were so active, God revealed to her that each boy—Esau and Jacob—would be the father of a nation but that the younger would be Isaac's heir (Genesis 25:19–28).
• Isaac did what Abraham had done with Sarah, claiming to Abimelech (a title for a king) that Rebekah was his sister. Abimelech discovered the truth and scolded Isaac, but then declared that “whoever touches this man or his wife shall surely be put to death” (Genesis 26:1–11).
• God's blessings ensured Isaac's crops and livestock flourished. The Philistines became jealous, and Abimelech requested that they leave. Isaac moved to the land where Abraham had dug several wells, also digging new wells. Isaac's servants dug one final well, and they founded the city of Beersheba (Genesis 26:12–33).
• Esau was Isaac’s favorite son, yet he sold his birthright (Genesis 25:31–34). Esau also married two Hittite women who made life bitter for both Isaac and Rebekah (Genesis 26:34–35). When it was time for Isaac to give his sons their blessing, Jacob and Rebekah deceived Isaac. Jacob received the birthright of the firstborn, and Esau received a promise that although his people would be wild warriors, they would eventually break out from under Jacob's rule (Genesis 27). Esau's descendants became the Edomites who brought the Israelites much trouble.
• Esau and Jacob reconciled in time to bury Isaac, who died at 180 years old. Isaac was buried in the same place Abraham and Sarah had been (Genesis 35:27–29; 49:29–32).
• Isaac is recognized as one of the patriarchs, along with his father Abraham and his son Jacob. God revealed Himself as the God of Abraham, Isaac, and Jacob and reminded the people of the covenant He had made with them (Exodus 2:24; 3:6, 15; 4:5; 6:3; 33:1; Leviticus 26:42; Deuteronomy 1:8; 34:4).

from the new testament

• Isaac is mentioned in Jesus’ genealogies (Matthew 1:2; Luke 3:34).
• Isaac is used as proof of the resurrection (Matthew 8:11). Matthew 22:32 and Mark 12:26–27 say that God is the God of Abraham, Isaac, and Jacob, and that God is the God of the living not of the dead.
• Isaac is used as evidence for a torment and paradise side after death where Isaac will be on the paradise side and evildoers will see him from the torment side (Luke 13:28).
• Peter and Stephen confirm Isaac’s place as a patriarch and that God revealed Himself as the God of Abraham, Isaac, and Jacob (Acts 3:13; 7:8, 32).
• The New Testament reveals that salvation comes by faith, not simply by being a descendant of Abraham. Twice, passages quote Genesis 21:12: “through Isaac shall your offspring be named” (Romans 9:7; Hebrews 11:18). God’s promise was fulfilled through Isaac, and the trust that He would do so revealed Abraham's and Sarah’s faith. Likewise, all those who trust in God’s promise of salvation through Jesus Christ are saved. All who reject it are not (John 3:16–18, 36; Romans 4).
• Isaac’s faith is recognized in Hebrews 11:20.

implications for today

God is the same yesterday, today, and forever (Hebrews 13:8). He keeps His promises and is faithful. Psalm 105 recounts how God kept His promise to Abraham through Isaac. When we do not trust in God to keep His promises, we take matters into our own hands, which creates problems for ourselves and for others. What would it have looked like for Abraham and Sarah to trust that God would provide a son? Instead of letting Abraham sleep with Hagar and having Ishmael, they would have trusted and waited for Isaac. However, God does not waste even our foolish mistakes. He kept His promise to Abraham and Sarah through Isaac, and He still keeps His promises today. We can trust in Him. We can trust His Word, by which we know Him and discover how He wants us to live. Although trust is sometimes difficult, it is not because God is not trustworthy. Sometimes we have to wait for God to answer or to see evidence of God at work, but His Word never fails (Deuteronomy 7:9; Isaiah 55:10–11; Matthew 24:35; 1 Peter 1:24–25).