‘You shall not misuse the name of the Lord your God,’ Exodus 20:7a
In this whole chapter God points out how - again and again - His Name is profaned by the disobedience and idolatry of His people. When they still were in Egypt, God already considered to pour out His wrath on them because they were captivated by the godless wisdoms of Egypt, more than by the God of Abraham (:8,9). But because of His oath given to Israel God led them out of Egypt and brought them to the land flowing with milk and honey.
In the whole history of Israel this has been no different. And in verse 39 and onward, the prophet ends with passing on these words of God. The translation may pose a problem, but what it boils down to is this: Go on, serve your idols but do no longer profane the holy Name of God! One of the worst sins is to misuse the Name of God. When someone misuses Gods Name in a curse, this is not as bad as paying lip service to God and pretending to trust in Him, but serving and trusting idols in daily life.
Everything in this life we put our trust in besides God, is an idol. If - in sickness - we entirely trust in human wisdom and only pray because it doesn't do harm, then we need a lot of salvation from pious, yet pagan idolatry. For then we misuse the holy Name of God.
But nobody will be able to understand how horribly we misuse God’s Name until God Himself will grant us mercy. Only then we will remember our conduct and all the actions by which we have defiled ourselves, and we will loathe ourselves, for only then we will understand how we have wronged our God.