四分律刪繁補闕行事鈔 2.230

2.230

Precept 38: Eating leftover overnight food. Three conditions: first, it is leftover overnight food; second, knowing it to be so; third, each swallow incurs an offense. In the Vinaya, leftover overnight food refers to that which was received today and kept until tomorrow; for all Śākya renunciants who have received the full precepts, it is impure. Discussing the four medicines, transgressing the limit incurs an offense as in the previous precept. The Samantapāsādikā, the Daśādhyāya-vinaya, and the Pañcavargika-vinaya state: When a fully ordained bhikṣu has received food, whether he has eaten of it or not, once the night passes it is called leftover overnight food.
Question: Are 'leftover' and 'overnight' the same or different? They are answered by the four alternatives: First, leftover but not overnight (if one has received the four medicines and without performing the verbal rite it passes midday), which incurs a duṣkṛta. Second, overnight but not leftover also incurs a duṣkṛta (meaning food not yet received, or kept overnight together, which is a duṣkṛta; if not kept overnight, there is no transgression). Third, both leftover and overnight, which incurs a pāyattika. Fourth, neither leftover nor overnight, as is obvious.
Leftover overnight and stored indoors also form four alternatives: First, leftover overnight but not stored indoors (food received today, kept outside the boundary, not stored together overnight, so it is not stored indoors), which incurs a pāyattika. Second, stored indoors but not leftover. The third and fourth alternatives may be known by analogy. Some say that on pure ground there is no storing indoors; but the text mentions excluding bhikṣus, so we know it exists.
In the Vinaya, the reason why the precepts against leftover overnight food and against taking unreceived food originated with meditating bhikṣus was to guard against evil bhikṣus of the future. Lacking internal contemplation of the Path, with afflictions not yet subdued, falsely relying on their spiritual work, they lightly dismissed the sacred precepts. This is because their minds were caught up in love and hate, and the great self was not yet cut down; therefore, practitioners of the three vehicles do not take the precepts lightly. Because they profoundly eradicate the root of the self and overthrow the banner of arrogance, revering the precepts to enhance spiritual practice, how could one not hold them in high esteem?