But this is incredibly obscure. I mean, no-one has ever heard of a phrase like ekaṁ samayaṁ bhagavā sāvatthiyaṁ viharati. O, wait … </sarcasm>
Thanks for pointing out what I should have recognized immediately!
Perhaps the nuance is to be found in a Sanskrit usage, where it can mean the “obscured” moon. In its current, and perhaps original, context, the verse is set on an uposatha, and earlier in the text we have several references to the sky:
abhikkantā, bhante, ratti; nikkhanto pacchimo yāmo; uddhasto aruṇo; nandimukhī ratti
So it’s not us covered by the clouds, it’s the sky. And we could translate:
It rains when the sky is hidden,
not when it’s revealed.
So reveal what’s hidden,
and it will rain no more.
I doubt if it’s germane to the translation, but it is interesting to note that, if we are correct, vivarati here has exactly the opposite of its ancestral Vedic meaning. One of the primal Vedic myths is of Vritra, the “dragon” (= ahi) who imprisons the waters, bringing drought to the land. Indra slays the dragon (vivarati) releasing the waters. The meaning of vritra as “constrictor” is still felt in the Pali nīvaraṇa.
While this is no more than a side note, it does point to another curious feature of the verse which is usually overlooked. Normally, especially in agrarian cultures, rain is a good thing. But here it seems to be considered a bad thing. However, it is not so straightforward. When Vritra holds back the waters you have a drought. But if he releases them all at once you get floods.
And in one place where ativassati is used with a clear contextual meaning, that’s exactly what it means. In Mil 6.3.1 we have ativassena dhaññaṃ vinassati.
Obviously “too much” is the most common meaning of ati. Equally, it might mean “on or over” as is usually interpreted here.
CPD hedges its bets, giving “excessive rain” for ativassa, but “to rain violently, to rain into or through” for ativassati, attested only in this verse (Cone has more references). It does seem a little unnecessary to posit two senses of a word for one context, when “rain too much” works perfectly well.
Comm. is ambiguous. It says that the positive use of ativassati does indeed mean too much (ativiya vassati), but in the negative form nātivassati the ati is a mere prefix.
The sense of “rain into” seems to be derived from the Ghatikara Sutta:
Atha kho, mahārāja, āvesanaṃ sabbantaṃ temāsaṃ ākāsacchadanaṃ aṭṭhāsi, na devotivassi
But this has variant readings. Perhaps we should read abhivassati with Mil here. (See Cone under ativassati and abhivassati).
In any case, the meaning of “rain on or into” is relevant only when the channa is the covered thing that the rains falls on. If it is, instead, the covered sky, then “rain too much” would seem to be better:
It rains too much when the sky is hidden,
not when it’s revealed.
So reveal what’s hidden,
and it won’t rain too much.
Oh, and I just noticed, that passage from the Ghatikara Sutta is relevant here, too. It says ākāsacchadana, which BB renders “open to the sky”, but literally it is “sky-covered”, i.e “the sky was its only roof”. (cp. English “sky-clad”=naked). This would seem to agree with our interpretation of channa.