From the Word
1 And God spoke all these words, saying, 2 “I am the LORD your God, who brought you out of the land of Egypt, out of the house of bondage. 3 “You shall have no other gods before me.
Exodus 20:1–3, RSV
The Jews abstained outwardly from idolatry, but their hearts were far from God, full of mistrust and unbelief. Outwardly they appeared beautiful, as though they meant it in all sincerity, but within they were full of idolatry. They understood this law to mean no more than that they should not set up idols and images to worship, and when they could confess with their lips that they have only one God and honor no other gods, they thought they had kept this commandment.
Now we must have high regard for the law. Thou, thou, it says, thou, and everything thou art; especially does it mean the heart, the soul, and all the powers. It does not speak of the tongue, or the hands, or the knees; but it speaks of the whole body and of all thou hast and art. If I am to have no other God, then I must surely possess the only true God with my heart, I must in my heart be affectionate to him, evermore cleave to him, depend upon him, trust him, have my desire, love and joy in him, and always think of him. Thou shalt love God with all thy heart, so that thy whole body from the crown of the head to the soles of the feet, inwardly and outwardly, goes forth in love, rejoices in God and honors him.
Now find me a man who is chaste and otherwise pious with a burning passion and love; there is none such on the earth. We find ourselves much more inclined to anger, hatred, envy, worldly pleasures. You see, you poor condemned creature, you should have delighted in God’s law, and you have no pleasure in it. Had we now remained in this condemnation, we would have had to perish forever. Therefore Christ comes and offers his mercy, and says: You are to love God with all your heart, but you have not done it; now believe in me. Then when we come before God the Father, Christ will say: Father! Although they have not wholly fulfilled thy law, yet I have done so, let this be to their benefit because they believe in me.
Luther, Martin, and John Sander. Devotional Readings from Luther’s Works for Every Day of the Year. Augustana Book Concern, 1915, pp. 311–12.