Exodus 20:7 Thou shalt not idly utter the name of Jehovah thy God; for Jehovah will not hold him guiltless that idly uttereth his name. (DBY)
Leviticus 19:16 Thou shalt not go up and down as a talebearer among thy people; neither shalt thou stand idly by the blood of thy neighbour: I am the LORD. (JPS)
Deuteronomy 5:11 Thou shalt not idly utter the name of Jehovah thy God; for Jehovah will not hold him guiltless that idly uttereth his name. (DBY)
Isaiah 58:13 If you keep the Sabbath with care, not doing your business on my holy day; and if the Sabbath seems to you a delight, and the new moon of the Lord a thing to be honoured; and if you give respect to him by not doing your business, or going after your pleasure, or saying unholy words; (See RSV)