Ex 20:7--You shall not take the name of the LORD your God in vain, for the LORD will not leave him unpunished who takes His name in vain.
LORD is a translation of the name of God, YHWH in the Bible text, because the Jews refused to use the name of God so as to be sure to avoid violation of the fourth commandment. Of course the name of God is recorded many times in the Bible, about 8000 times, and God would not have given us His name if He did not intend for us to know it and to honor it. But the scribes of the Bible refused to write His name, so we do not know the name today. Perhaps Yahweh is the closest Anglicized version of the name of God. The important thing is that we respect the Creator who is represented by the name.
With the birth of Jesus Christ, we were given a new name to honor. Jesus is the only name given among men whereby we may be saved, Acts 4:10-12--Let it be known to all of you and to all the people of Israel, that by the name of Jesus Christ the Nazarene, whom you crucified, whom God raised from the dead -- by this name this man stands here before you in good health.
He is the STONE WHICH WAS REJECTED by you, THE BUILDERS, but WHICH BECAME THE CHIEF CORNER stone. And there is salvation in no one else; for there is no other name under heaven that has been given among men by which we must be saved.
Therefore the third commandment applies to the name of Jesus. We should not curse in the name of Jesus, unless we want punishment. In fact, if we fail to respect Jesus, we will receive damnation.
Respect for Jesus is in short supply in the American Culture, and in Europe, and everywhere that mankind thinks that he is in control of his own destiny. Unrighteousness, lack of respect for the Source of all life, has led to the fall of many kingdoms and societies.
Disrespectful talk is representative of an underlying lack of respect for other people and for God. My mother was very careful about the speech of her children. Once she put Quinine in my mouth for saying a bad word. I have heard of washing children’s mouth out with soap for saying unacceptable words, but Quinine’s bitter taste is a step beyond soap. I learned to be careful about my speech.
But the fourth commandment is about more than loose language. It focuses upon the practice of people vowing certain action in the name of what is holy to them. It was common practice for idolaters to make vows in the name of their so-called gods. God wanted his people to be more careful about respect for the true God.
Jesus spoke about the third commandment in the sermon on the mount, Matt 5:33-37--Again, you have heard that the ancients were told, ‘YOU SHALL NOT MAKE FALSE VOWS, BUT SHALL FULFILL YOUR VOWS TO THE LORD.’
But I say to you, make no oath at all, either by heaven, for it is the throne of God, or by the earth, for it is the footstool of His feet, or by Jerusalem, for it is THE CITY OF THE GREAT KING. Nor shall you make an oath by your head, for you cannot make one hair white or black.
But let your statement be, ‘Yes, yes’ or ‘No, no’; anything beyond these is of evil.
It was likely because of respect for God and the uncertainty of our own future that led to the saying "If the Lord is willing, I will do this or that." Someone added "And if the creeks don’t rise." Surely the rising of creeks is within the will of God, and so we should be content to say as a condition of prediction "If the Lord is willing."
It is important for our blessed existence for us to encourage each other to respect the name and power of God. We should encourage our children, grandchildren, friends, and family to speak respectfully of Jesus. Using Jesus as a by word or curse word is a sure sign of lack of understanding what is holy and righteous and true.