Musāvādasutta
“Catūhi, bhikkhave, dhammehi samannāgato yathābhataṁ nikkhitto evaṁ niraye. Katamehi catūhi? Musāvādī hoti, pisuṇavāco hoti, pharusavāco hoti, samphappalāpī hoti— imehi kho, bhikkhave, catūhi dhammehi samannāgato yathābhataṁ nikkhitto evaṁ niraye.
Lying
“Mendicants, someone with four qualities is placed in hell as if delivered there. What four? They use speech that’s false, backbiting, harsh, or nonsensical. Someone with these four qualities is placed in hell as if delivered there.