Shiva Purana
पैशुन्यं कूटवादश्च साक्षिमिथ्याभिलाषिणाम् । एवमादीन्यसंख्यानि पापानि विविधानि च। सद्य एव विनश्यंति त्रिपुंड्रस्य च धारणात् 1-24-६०।
Backbiting, false accusations, desiring false testimony, and other such sins are instantly destroyed by the wearing of the Tripundra (three marks of ash) on the forehead.
english translation
paizunyaM kUTavAdazca sAkSimithyAbhilASiNAm । evamAdInyasaMkhyAni pApAni vividhAni ca। sadya eva vinazyaMti tripuMDrasya ca dhAraNAt 1-24-60।
hk transliteration by Sanscript