What does Genesis 25:21 mean?
Once again, both barrenness and God's intervention play a role in the birth of the next generation in the line of God's people. Rebekah remained barren for a time, unable to have children. Isaac's mother, Sarah, remained childless until she was 90 (Genesis 17:17; 21:1–2). We're not told how much time passed between Isaac's prayer and Rebekah's pregnancy, but we do learn that Isaac was 60 when his sons are eventually born. That means the couple remained childless for 20 years.The important thing to note is that Isaac took action. Prayer is action. He prayed to the Lord for his wife. God responded to Isaac's prayer. God had promised that multitudes would come from Abraham, but each birth in the line of God's chosen people thus far seems to have required special intervention from God Himself to take place. God's people understood that their children were gifts from Him.