Tell me, you who desire to be under the law, do you not hear the law? For it is written that Abraham had two sons: the one by a bondwoman, the other by a freewoman. But he who was of the bondwoman was born according to the flesh, and he of the freewoman through promise, which things are symbolic. For these are the two covenants: the one from Mount Sinai which gives birth to bondage, which is Hagar—for this Hagar is Mount Sinai in Arabia, and corresponds to Jerusalem which now is, and is in bondage with her children—but the Jerusalem above is free, which is the mother of us all. For it is written:
“Rejoice, O barren,
You who do not bear!
Break forth and shout,
You who are not in labor!
For the desolate has many more children
Than she who has a husband.”
Now we, brethren, as Isaac was, are children of promise. But, as he who was born according to the flesh then persecuted him who was born according to the Spirit, even so it is now. (Galatians 4:21-29)
Abraham had Ishmael, his first son. He loved him, but he was not the one to be the heir of God. Once Isaac was born, Ishmael bullied Isaac. Sarah saw it and knew they couldn’t live together. Paul says they represent the law and grace—Ishmael, the law and Issac, grace. Often, we want to live holy lives so we can manufacture a legal system to give us brownie points for doing good. This system will always mock what God wants to do through grace. It will have to be cast out, like Abraham had to cast Ishmael out. The flesh and the law had to go. We cannot allow any of the law to stay in our hearts or it will spoil grace.
Grace says God loves us, even if we don’t pray enough, even if we cuss someone out, even if there is chaos in the home. We are saved by grace and it makes us stronger. Too many of us are bewitched and trying to serve God out of our flesh and not out of grace. We can only please God by faith. We don’t want to add anything to it. The law was our tutor at one point, showing us that we need a Savior. Once we receive Christ, we don’t need to live by that constraint anymore. We live by grace.