Dies ille, dies irae?

In approaching the translation of the Latin text:

Dies ille, dies lunæ
Semper venit opportune
Rogo vos et quæro id
Quid est quod et quod est quid?

One must bear in mind the considerations which are necessary in order to obtain a good and proper understanding of the text in its original context. Among these are the precision with which Latin words are used, and the considerable depth of allusion that would be commonly found in such texts. It is not therefore simply a matter of taking the words as they come, but giving appropriate weight to each one in its context and its usage elsewhere in the Latin world. A good starting point is however a literal translation, unless there is so obviously a special meaning to be attributed to a particular set of words, as in a common metaphor or simile. So a literal translation could be

That day, day of moon
Always comes opportunely
To ask of you and it to query
That is this and this is that.

Now dies is more specifically associated with daylight rather than the twenty four hours that we would think of as day, but dies illa is found elsewhere in the literature in the context of mourning for the day of burning judgement – heat may be easily understood from this, but given that judgement is not to be found elsewhere in the text the idea of judgement, though implied, must be considered a foreign element and the use of the phrase dies ille to have a different allusion in mind, for example the burning that one feels, not from judgement but from the sun when it is in the height of its ascent, which naturally occludes with dies meaning daylight. That the repetition in the first line almost exactly corresponds with the well known words ‘dies iræ, dies illa‘ which may be found elsewhere suggests that there is a gentle pun to be found in here, so we must be careful not to miss this when we settle for our final form of English words. Dies lunæ of course is easily recognised by us. It is not, if we are clouded in our thinking by the twenty four hour idea of day as we may conclude that part of the day that is governed by the moon, which we would normally consider to be night time, but rather it is the day of the moon which is that day of the week which is known to us as Monday. Working through the text with such things in mind and similar considerations, we can then readily understand that the only faithful rendition of the ideas found in this Latin text when expressed in English is:

On Monday, when the sun is hot
I wonder to myself a lot:
‘Now is it true, or is it not,
That which is which or which is what?’

_{Commentary © 2009 Chocolate from an original text by AA Milne © 1926, Latin text © 1960 Dr Alexander Lenard}