Taking God’s name in vain is a serious offense: Jehovah will not hold anyone guiltless who takes His name in vain. (Ex 20:7) He introduces this concept in the Decalogue as the last command of three relating how we’re to treat God Himself. What does it mean, to take God’s name in vain?
Traditionally, it appears to have been understood to mean we’re not to speak or write God’s name inappropriately, which is certainly dishonoring to God. (Ps 139:20) Yet a careful look at the text itself indicates this is not the whole of the matter; it is perhaps only periphery.
The command does not refer to speaking or writing God’s name, but to taking His name, taking it up, bearing it, carrying it along. The Hebrew is נָשָׂא, nasah, to bear. Cain chooses this word in his complaint, “My punishment is greater than I can bear.” (Ge 4:13), and God uses it to describe how the high priest continually bears the names of Israel upon his heart in the breastplate (Ex 28:29), and also how he bears their judgment before Jehovah. (30) So, taking Jehovah’s name seems to be more about taking it upon one’s self, associating and personally identifying with it … with Him.
So, what then does it mean to take up Jehovah’s name, or to associate ourselves with it, in vain? Vain is the Hebrew שָׁוְא, shav, meaning empty, false, deceitful. It is used in the command to not raise a false report, to mislead and give the wrong impression. (Ex 23:1)
Thus, taking God’s name in vain is to falsely identify and associate ourselves with God by appealing to His name and character when we aren’t submitted to Him, not loyal to Him, not faithful to Him. It would include speaking on His behalf when He hasn’t called us to do so and told us what to say. (De 18:20) It also would describe identifying ourselves as God’s servants or representatives under false pretenses or ulterior motives, to gain the respect of and/or otherwise influence, manipulate or control others, using God to benefit ourselves; this is the heart of all false religion.
When the disobedient become impostors, infiltrating the Faith, presenting themselves as Christ’s disciples and servants (2Co 11:15), they evidently do more harm to the name and reputation of God (Tit 2:5) than those who merely speak or write His name in appropriately. When we falsely represent Him to others, who then associate God Himself with our sins and indiscretions and blaspheme Him because of us. (Ro 2:24), God will not overlook this; He will hold each of us accountable for how we leverage and exploit our relationship with Him.