>>22371
"Swearing to God" is taking the lord's name in vain. That's a sin.
>You shall not take the name of the Lord your God in vain, for the Lord will not hold him guiltless . . . (Exodus 20:7, HBFV, which is similar to the KJV, NKJV and other translations)

>You shall not misuse the name of the Lord your God, for the Lord will not hold anyone guiltless . . . (NIV, which is similar to the HCSB, CEV, NLT and other translations)