DEUT1555 Out of reverence for His Name, [a person who loves God] must be aware of all that might bring him to swear in the Name of the Creator, may He exalted, [whether] to affirm what is true or refute what is false, and certainly not to affirm what is false or refute what is true, as it is written: “He who has clean hands and a pure heart, who has not sworn falsely by My Name or sworn deceitfully” (Tehillim 24:4); “To fear this glorious and awesome Name” (Devarim 28:58) ; “But the sunrise will bring salvation to you who fear My Name, with healing in its wings” (Malachi 3:20). Our sages, of blessed memory, said [of the last verse]: “’You who fear My Name’ refers to people who fear to utter the Name of God in vain” (Nedarim 8b). “Curses” include revilement, vilification, and insults in which God's Name is mentioned. This is exceedingly disgraceful in a believer; yet the masses permit themselves this practice to a most reprehensible degree. Their intention [in mentioning God’s Name] is to dramatize and exaggerate in their vilification and heighten and embellished their insults. In this they embody what the Wise One said: “To a fool it is like sport to commit an indecency” (Mishlei 10:23). It is also said: “Every mouth speaks impiety” (Yeshayahu 9:16); “The tongue of a righteous man is like pure silver” (Mishlei 10:20).