Scripture addresses the content and purpose of speech comprehensively but does not provide a specific prohibited-words list. The biblical framework: unwholesome speech that tears down rather than builds up is sin (Ephesians 4:29); coarse joking (aischrologia) is prohibited (Ephesians 5:4); taking God's name in vain is the third commandment; and the tongue reveals the heart (Matthew 12:34). 'Cussing' is not one thing — blasphemy, crude sexual humor, and culturally offensive words are in different biblical categories. 45/100 Caution.
Ephesians 4:29 is the clearest text: "Do not let any unwholesome talk come out of your mouths, but only what is helpful for building others up according to their needs, that it may benefit those who listen." The Greek word translated "unwholesome" (sapros) means rotten or decaying — speech that corrupts rather than builds. This is the fundamental principle: the test is whether speech builds up or tears down, not whether a word appears on a cultural prohibited list.
Ephesians 5:4 prohibits "obscenity, foolish talk or coarse joking" (aischrologia, morologia, eutrapelia) — crude sexual humor and vulgar speech that reduces human dignity. This directly addresses what most people mean by "cussing" in a social context.
The third commandment — "You shall not misuse the name of the LORD your God" (Exodus 20:7) — specifically prohibits using God's name carelessly or as an expletive. "OMG" and "GD" fall clearly within this prohibition, which is notably the only specific speech commandment in the Decalogue.
Many words considered "cuss words" in American English are culturally specific — their offense-level varies by context, culture, and generation. Paul uses the Greek word skubalon (translated "garbage" or "rubbish" in most English Bibles) in Philippians 3:8 — a word whose vulgarity in Greek is closer to our English equivalent of sh** than a polite term. This suggests Paul was not above emphatic language. The biblical concern is with the character and purpose of speech, not conformity to a cultural taboo list.
The practical test for a Christian: does this speech build up or tear down? Does it reflect a heart submitted to God? Does it use God's name carelessly? Does it reduce human dignity? These questions are more biblically grounded than asking whether a word appears on a list. See the Gospel Coalition's treatment of swearing for additional biblical analysis. See our Is It a Sin? hub and our guide on Is Drinking Alcohol a Sin?
For the broader biblical framework on honesty and deception, see our guide What Does the Bible Say About Lying?