Genesis 21:1-2 describes the fulfillment of God's promise to Abraham and Sarah with the birth of Isaac. Hebrews 11:11 highlights Sarah's faith in God's promise, emphasizing the faithfulness of God in fulfilling His word.
Genesis 21:6 records Sarah's joy and laughter at the birth of Isaac, which parallels the joy and celebration at the birth of John the Baptist in Luke 1:58, highlighting the theme of divine intervention and joy in God's promises.
Genesis 21:10 describes Sarah's demand to cast out Hagar and Ishmael, which Paul references in Galatians 4:30 to illustrate the distinction between the children of the promise and the children of the flesh.
Genesis 21:12 emphasizes that Isaac is the child through whom Abraham's offspring will be reckoned, which Paul cites in Romans 9:7 to discuss the concept of spiritual lineage and God's sovereign choice.
Genesis 21:17 shows God hearing the cries of Ishmael, which is echoed in Psalm 34:17 where it is stated that the Lord hears the cries of the righteous and delivers them from their troubles.
Genesis 21:33 refers to Abraham calling on the name of the Lord, the Everlasting God, which is a theme echoed in Isaiah 40:28, where God is described as the everlasting Creator who does not grow weary.