四分律行事鈔資持記 3.511

3.511

三中。彼以針綴衣，無故衣解形露，因制帶行。今用鉤紐，則不須之。此中但明聽畜耳。

In the third: that [monk] fastened his robe with a needle; without cause the robe came undone and his body was exposed, which led to the prohibition [against sewing it shut] and permission to wear a belt when traveling. Nowadays, hooks and loops are used, so this is not needed. Here it only explains that keeping them is permitted.