Levítico 18

Levítico 18:5

The righteousness of the law, of which it is said that if a man does it he shall live in it, is set forth to this end: that every man may recognize his own infirmity. It is not in his own strength or through the letter of the law (which cannot be) but only by receiving through faith the favor of the Justifier that he may attain and do and live in righteousness. — ON THE SPIRIT AND THE LETTER 29.50