When I was growing up, I was told to use God’s name in church, prayer, or other spiritual contexts, but to say “God” in an irreligious way—after stubbing a toe or losing a game—was to break the commandment: “You shall not take the name of the Lord your God in vain” (Exod 20:7). While I still refrain from saying “God” outside of religious discourse, this verse doesn’t mean what I was told growing up. When the Bible proscribes taking the Lord’s name in vain, it does not refer to saying “God” as an exclamation or expletive; instead, it prohibits invoking the divine name in an oath, and then failing to fulfill that oath.
In ancient Israel, an oath was a solemn statement that began חי־יהוה (chai Adonai)—“as the Lord lives”—and meant: “If I don’t fulfill the following oath, may the Lord who lives strike me dead!” For example, after Jonathan convinced Saul not to kill David, “Saul swore, ‘As the Lord lives (חי־יהוה; chai Adonai), he shall not be put to death’” (1 Sam 19:6). Saul’s oath means that if David dies at Saul’s hand, then Saul also deserves to die.
The Hebrew word commonly translated “take” in Exod 20:7 is נשא (nasa), meaning to “bear” or “lift up.” Invoking God’s “name” (שׁם; shem) means bearing it, just like Aaron was to “bear” (נשא; nasa) the names (שׁמות; shemot) of the Israelites” on his breastplate (Exod 28:29). As a bearer of God’s name, the oath-taker must accomplish the sworn oath, or else…. Yeshua protected his followers from taking God’s name in vain when he said to “not swear at all” (Matt 5:34) – that way, you’ll never swear an oath that you might not fulfill, so you can rest assured that you’ll never break the commandment!