四分律刪繁補闕行事鈔 1.183

1.183

二明開遮。律中唯除結界，餘並開之。雖非明文，以非制故。

Second, clarifying allowances and prohibitions. In the Vinaya, with the sole exception of demarcating the boundary, all other [acts] allow it. Although there is no explicit text, it is because it is not instituted [for boundary demarcation].