Genesis 21:9-12 "And Sarah saw the son of Hagar the Egyptian, which she had born unto Abraham, mocking. 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. And the thing was very grievous in Abraham's sight because of his son. And God said unto Abraham, Let it not be grievous in thy sight because of the lad, and because of thy bondwoman; in all that Sarah hath said unto thee, hearken unto her voice; for in Isaac shall thy seed be called."
The promised son, Isaac, had survived infancy and grown to the point that Sarah was able to wean him. He was ready to begin to take on more solid sustenance to continue his growth and development. In celebration of this fact, Abraham made a great feast. Hagar and Ishmael were present, and trouble was present with them.
Ishmael was seen mocking Isaac. Since Ishmael would have been in his mid-teens by this point, it is highly likely that he understood the ramifications of Sarah having a son with Abraham. Ishmael could very easily have felt threatened by Isaac. He was concerned about losing his father’s affection as well as losing his status as the firstborn.
The scripture does not tell us if Ishamel was simply making fun of Isaac or if he was behaving in a threatening manner. Either way, Sarah was having no part of it. The Hebrew word translated as “cast out” means “to drive out from a possession or to divorce.” Hagar and Ishamel were to have no standing in Abraham’s household.
This was exceedingly difficult for Abraham. Ishamel was his son, and he obviously loved him. However, Ishamel was not the seed that God had promised. Rather, he was the result of Abraham’s failure to wait on the LORD. Abraham was now reaping the result of failing to wait.
When we take matters into our own hands rather than trusting God, we may find ourselves in a situation that is hard to let go of. We risk becoming enamored of the result of our unbelief. It may be difficult for us to see the need to divorce that thing from our lives. Even when someone we love (as Abraham loved Sarah) calls it to our attention, it may still be grievous to us.
However, the word of God spoke peace to Abraham concerning the need to cast out the bondwoman and her son. God told Abrham that this thing was not to be grievous to him. Abrham was instructed to listen to what Sarah had said. Ishmael was never intended to be heir with Isaac. Abraham’s seed was always to be of Isaac’s lineage.
In order to truly serve God, we must divorce from our lives the things of the flesh. This is what the apostle Paul was alluding to when he declared that “our old man” is crucified with Christ. By God’s grace, we can do this with joy for the fulfillment of the promise. May we be blessed to hearken to the voice of God in our lives.