Contradiction with Genesis 16:15
This verse explains that Hagar bore Abram a son, Ishmael, who is actually Abraham's first son, which could contradict the focus on Isaac in Genesis 17:21.
Genesis 16:15: And Hagar bare Abram a son: and Abram called his son's name, which Hagar bare, Ishmael.
Contradiction with Genesis 21:10
This verse highlights Sarah’s demand to cast out Hagar and Ishmael, which opposes the idea of inclusivity in Isaac's covenant.
Genesis 21:10: Wherefore she said unto Abraham, Cast out this bondwoman and her son: for the son of this bondwoman shall not be heir with my son, [even] with Isaac.
Contradiction with Romans 9:7
It states that not all of Abraham's children are counted as his seed, which might seem to contradict the promise to Isaac in Genesis 17:21, as it suggests a broader interpretation.
Romans 9:7: Neither, because they are the seed of Abraham, [are they] all children: but, In Isaac shall thy seed be called.
Contradiction with Galatians 4:23
It contrasts Ishmael as born after the flesh and Isaac as born through promise, indicating divergent paths rather than the unified promise to Isaac.
Galatians 4:23: But he [who was] of the bondwoman was born after the flesh; but he of the freewoman [was] by promise.
Paradox #1
Genesis 17:21 could possibly raise questions due to the timeline and promises made to Abraham about his sons, Isaac and Ishmael. Some readers might point out that there seems to be different accounts or emphasis in other parts of Genesis regarding God's covenant and promises to Ishmael and Isaac, leading to potential confusion or perceived inconsistency about the roles and blessings designated to each.