四分律行事鈔資持記 3.800

3.800

八戒，初科。《多論》開心念者，即自誓受；疏云：非謂常途，故彼文云：若無人時，得心念受，明緣開也。

Regarding the eight precepts, the first section: The Sarvāstivāda Vinaya Vibhāṣā's permitting mental reception refers to receiving them by one's own vow. The Commentary says: "This does not refer to the regular procedure." Therefore, that text says: "When there is no one present, one may receive them mentally," clarifying that this is permitted under special conditions.