"You shall not take the name of the LORD your God in vain, for the LORD will not hold him guiltless who takes his name in vain.
Exodus 20:7
The prohibition in the third commandment is against a wrongful use of the Divine Name in the making of oaths, as seems clear from our Lord's comments in Matthew 5:33-37, that is, false swearing as well as vain or profane swearing. To invoke the name of God is to involve His character, and therefore to take it in vain is to insult His majesty and glory. This is a word of wide application, not only in the careless use of the Divine Name in the unthinking expostulations of secular speech (as is regrettably common) but also in what can only be called the 'religious jargon' that is prevalent in so much Christian conversation nowadays. This is also a careless and indiscriminate misuse of the Lord's name which violates the commandment because it is used unthinkingly. One thinks of the 'Praise the Lord' attitude, so rife and so irreverent on many lips that has debased a noble and worshipful attitude of heart and spirit, and made it an offence to thoughtful people. To mouth a meaningless 'Praise the Lord' on every conceivable occasion is not necessarily a sign of grace in the soul. One recalls men in the Forces during the war who could not speak four words without an ugly, filthy swearword. This in them was often not so much a sign of depravity as of lack of intelligence and ability to speak the English language - a lack of ordinary vocabulary. So it often is with this unthinking and irreverent larding of conversation with religious phrases and exclamations, and it can only be called taking the name of the Lord in vain. There was the man, for example, who unthinkingly said, 'Praise the Lord' when hearing of a sorrow and tragedy. True, one learns to praise the Lord in sorrow, but you do it, not say it unthinkingly. Jesus did not say, 'Praise the Lord' at the grave of Lazarus; He wept. There is something very important and fundamental to learn in that.