Sifre Deuteronomy on Spelling in a Torah Scroll

And inscribe them [ketavtam] (Deuteronomy 6:9)—with perfectly formed letters [ktav shalem]. On this basis they taught: If the copyist of a Torah-scroll wrote alephs as ayins or ayins as alephs; or bets as kaphs or kaphs as bets; or gimmels as tzaddis or tzaddis as gimmels; or dalets as reshes or reshes as dalets; or hehs as khets or khets as hehs; or vavs as yods or yods as vavs; or zayins as nuns or nuns as zayins; or tets as pehs or pehs as tets; or bent letters as straight letters or straight as bent; or mems as samekhs or samekhs as mems; or closed letters as open letters, or open as closed—if he wrote a closed paragraph as an open paragraph, or an open paragraph as a closed paragraph; or if he wrote without using black ink, or if he inscribed the Song [at the Sea (Exodus 15)] like the surrounding [prosaic] verses; or if [contrary to scribal conventions,] he inscribed the Divine Epithets with gold—indeed, any scroll so inscribed should be hidden away.¹