制斷蚕帛緣起
Origin of the Prohibition on Silk
鈔(中二)引四分云。因比丘至養蚕家。乞未成已成緜作三衣。便待看暴蠒作聲。因訶制云。若純作。若雜以毳劫貝。若麻及餘縷雜作成者。若斤斧細剉。和泥塗壁及埵。乃至僧祇云。紐揲經緯穿雜者。一切捨墮。受用得越。
The Commentary, second section, cites the Four-Part Vinaya: Because monks went to the houses of silk-rearers and begged for raw silk, whether finished or unfinished, to make the three robes, and even waited to watch silkworms being boiled alive and hear their cries, the Buddha accordingly rebuked them and laid down the rule: If a robe is made purely of silk, or mixed with wool or cotton, or made mixed with hemp and other threads, or if silk is chopped fine with axe and knife and mixed with mud to plaster walls and pillars—and even as the Saṅghika says, if it is knotted, folded, woven warp and woof, or threaded through and mixed—then all such [use of silk] is an offense requiring expiation and forfeiture; using it is a minor transgression.