Oh, this is a law that many don't know the principle behind or really what it is all about. Using the Lord's name is like saying "by the honor of my family name, I will finish this mission" you have sworn an oath to uphold His honor, not just yours. So why do we use his name so easily? Because we probably don't know what the principle behind the Law is about. If you don't want anyone smearing your reputation by using your name then we should be just the same with our God. God cares for us we should do the same. Stay blessed!