What should a believer do with legalism after understanding the Gospel of Grace?
Once a believer understands the Gospel of Grace, he should cast out legalism entirely. Scripture pictures legalism as the bondwoman and her son, who cannot be heirs with the free woman. Like Abraham and Sarah sent Hagar and Ishmael into the desert, legalism must be expelled, not tolerated or mixed with grace.
Les explains that the bondwoman and her son are a picture of legalism. He says he hates and detests legalism because God does. The admonition of Scripture is that once you understand this Gospel of Grace, you cast legalism out, just exactly like Abraham and Sarah sent Hagar and Ishmael into the desert. The son of the bondwoman shall not be an heir with the son of the free woman, and believers are not children of the bondwoman but of the free. This was a beautiful picture.
Nevertheless what saith the scripture? Cast out the bondwoman and her son: for the son of the bondwoman shall not be heir with the son of the freewoman.