Which covenant are you living under?
Paul asks a decisive question in Galatians 3:2: Does God give you His Spirit and work His power among you because you observe the law, or because you believe what you heard?
To observe the law is to appeal to what we must do. In that framework, God’s act of giving His Spirit and working His power among us becomes conditional, dependent on whether we have fulfilled our part of the equation. This is the concept Paul is referring to when he quotes Leviticus 18:5 in Galatians 3:12 and Romans 10:5.
By contrast, to believe what you heard is to experience, through no action of your own, an expression of God towards you. Authoring and finishing our faith are God’s gracious actions toward us. Because they rest on Him rather than on us, they are unconditional. They do not require us to do anything first, such as “choose to believe” or “choose to accept,” since those actions fall under the category of what “we must do.”
This contrast runs throughout Galatians. Paul repeatedly distinguishes between what depends on human action and what depends entirely on God’s action. For example:
1. Observing the law is something you must do; believing what you heard is the work of God. Galatians 3:2, John 6:29
2. The desolate woman having more children than the woman with a husband is not the result of human action; it is something only God can bring about. Galatians 4:27
3. Being born of the slave woman is according to the flesh, while being born of the free woman is according to His promise. Paul identifies these as the two covenants: “according to the flesh” represents the Old Covenant of what we must do, while “according to His promise” represents the New Covenant of what He does. Galatians 4:21–24
Therefore, in Galatians 3:2, observing the law refers to the Old Covenant, while believing what you heard—faith—refers to the New Covenant. Faith, then, is the work of God, not a choice you must make, or a gift you must receive.
In short, the Old Covenant operates on the basis of what you must do; the New Covenant operates on the basis of what God has done and will do. This is the central message Paul presents in Galatians. Because Christian/Catholic orthodoxy makes your salvation, favor, and blessing from God depend on what you do, then the question must be asked: which covenant does that belong to? More personally, which covenant are you living under?