I was struggling with the Pali term pātabyata, and thanks to Ven @Brahmali I can understand it better now. The following remarks are largely expanded from his notes to me.
It occurs in two main kinds of contexts. In the Vinaya Pc 11 we find
Which means something along the lines of “destroying plants”. However in the suttas we find, eg. at AN 3.113:
kāmesu pātabyataṃ āpajjati
Which Ven Bodhi translates as “falls into indulgence in sensual pleasures.”
The term is missed in the PTS Dictionary. In his Analysis of the Bhikkhupatimokkha, Ven Nyanatusita discusses the term in some detail, showing that it is likely derived from a causative of √pat, “to fall”. He suggests it is a double abstract, with analogy to sahavyatā, metteyyatā, etc. and translating “they come to ruin [by indulging] in sensual pleasures.”
Ven Brahmali remarks that “fall upon” works reasonably in all contexts. When referring to sensual pleasures, it would be an idiom, whereas with living beings a more literal understanding would be required.
He further remarks that the sentence construction at MN45 doesn’t yield the best sense by understanding it as “falls to ruin on account of sensual pleasures.” The Pali reads:
Te kāmesu pātabyataṃ āpajjitvā kāyassa bhedā paraṃ maraṇā apāyaṃ duggatiṃ vinipātaṃ nirayaṃ upapajjanti,
Which would then mean, “having fallen to ruin on account of sensual pleasures, after death he is reborn in a bad destination.” But the falling into ruin is precisely the bad rebirth; there should be no temporal sequence here, but this is required by the absolutive verb.
In DN27 (Aggañña Sutta) we find:
Yato kho te, vāseṭṭha, sattā tasmiṃ asaddhamme ativelaṃ pātabyataṃ āpajjiṃsu,
“Because, Vāsettha, those beings too often fell upon that unrighteous practice [referring to sexual intercourse].”
Here the context is not monastics going to hell, but ordinary people gradually going downwards. Understanding this as going to ruin seems too strong.
Moreover, the locative is quite commonly used to express relation “about/in regard to,” but it is less often used to express cause “on account of.” In fact the causal meaning of the locative is really just an extension of the relational meaning, see Wijesekera. So the relational meaning is more likely to be the correct one.
The English idiom “fall on” or “fall upon”, by a curious coincidence, covers exactly these two cases:
- attack fiercely or unexpectedly.
“the army fell on the besiegers”
- seize enthusiastically.
“she fell on the sandwiches as though she had not eaten in weeks”
I don’t think we can actually use this idiom, but it does clarify how these two senses can arise from the same phrase:
falling upon (i.e. attacking, destroying) plants
kāmesu pātabyataṃ āpajjati
falling upon (i.e. indulging in) sensual pleasures
So it seems that Ven Bodhi’s latest rendering, “falls into indulgence” works well for such cases; a different rendering is required for the Vinaya, however.