The law is nothing but a manifestation of the will of God. As the will of God is eternal, so also is the law. Consequently we are speaking here only of the law which is conducive to the godliness of the inner person. That is indeed nothing
other than a manifestation of the divine will. For example, this law: “You should love your neighbor as yourself” [Leviticus 19:18; Matthew 22:30] is nothing but the law of nature that says “Whatever you want done to you, do also to another” [cf. Mt. 7:12; Lk. 6:31] and conversely: “What you do not want, do also to no one” [Tobit 4:16]. Yes, this law of nature, which God made sweet with love, must only come from God. And although the heathen also accept it, it nevertheless does not come from human reason—let them say what they want. For this same reason only considers
itself and does not hold that it should show consideration for others, but that others should show consideration for it.
Therefore all laws which make the inner person godly can be from no one but God. However, understand: laws do not
have the power to make a person godly or righteous; rather, they point out only how a person should be if he wants to
live according to the will of God, become godly and come to God. According to Romans 7:12, “The law is holy and the commandment is also holy.” Now it cannot be holy unless it comes from one who is holy. Insofar as it came from us it would not be holy, for we are not holy. Therefore Paul says again soon after: “We know that the law is spiritual” [Rom.
7:14]. However, if we are carnal, then it is obvious that the law cannot be from us. All this proves that the law which teaches the true inner godliness must flow alone out of the divine will (Zwingli’s Short Christian Instruction [1523]).