DEUT1513 If one completely disregards the prohibition of lashon hara, Heaven forbid, and does not resolve to guard against transgressing it, then he incurs a third curse, that of אָר֗וּר אֲשֶׁ֧ר לֹא־יָקִ֛ים אֶת־דִּבְרֵ֥י הַתֹּורָֽה־הַזֹּ֖את לַעֲשֹׂ֣ות אֹותָ֑ם, “Cursed is one who does not uphold the words of this Torah, to do them” (Devarim 27:26). This curse refers to one who does not resolve to keep the entire Torah. One who completely disregards the prohibition of lashon hara is referred to as a mumar l’davar ehad, since he flagrantly violates this severe prohibition and views this aspect of Hashem's Torah as inconsequential, similar to a mumar who disregards the entire Torah. His sin is therefore unbearably severe.