I'm translating a text from Sanskrit, which has a singular/plural (and, actually, dual) distinction in the second person. It has long been the custom in English translation to render the 2nd singular with 'thou', etc. and the 2nd plural with 'ye/you', etc., as in Early Modern English (EModE). This creates a suitably archaic and liturgical feel to the translation.
But I've come unstuck with the phrase 'may you be covered'. If I want to replace 'you' with 'thou', should 'may' become 'mayest' or not?
My feeling is that 'may' is functioning as an auxiliary here. In Modern English, we say 'he likes it', but 'may he like it'. We do not say 'mays he like it', the 'may' is not a finite verb. So I would expect the same to apply to EModE.
However, we would also apply the same logic to 'should'. We would say 'Has he eaten of the tree, whereof I commanded him that he should not eat?', not '... that he shoulds not eat?'. And so I would have expected, applying that logic, to find '... that thou should not eat?'. And yet we have in Genesis:
And he said, Who told thee that thou wast naked? Hast thou eaten of the tree, whereof I commanded thee that thou shouldest not eat?
Which leads me to question whether the may would be finite and agree with thou, or not. Should it be 'mayest thou be covered' or 'may thou be covered', and why? This, to be clear, is in the sense of an imperative: 'Be covered!' - only softer.