The dictionaries are very clear as to the use of "may" to express a wish or a hope - and one can easily infer that a sense of future is always implied in such use. For example: "May she rest in peace"; "May you achieve all you wish"; "May the Force be with you". However, when it comes to expressing someone's wish or hope in a past situation, it seems to me the use of "might" - which would be a "natural substitute" to the word "may" - sounds somewhat strange. Let's take the following example: "I was going through the most difficult moment of my life. Might God help me!". Is the use of "might" correct in this sentence? If not, what would be the right way to express such hope/wish in the past?
I think a little grammatical clarity is needed:
First of all:
"May she rest in peace". is uttered at a present time. It is a spoken phrase.
In the unusual case that one wants to report on that (reported speech), one could say:
"She was laid gently in the grave so she might rest in peace."
In that instance, might is not really the past tense of may. As May [head word] in a sentence is not a modal verb. might rest in peace = have the possibility of resting in peace, is a modal and here, it is in the past tense.
Present tense: She may rest in peace if laid gently in the grave. Tricky wicky is what this is.
In in terms of the OP's question, let's put it in the present tense:
"I am going through the most difficult moment of my life. May God help me!".
That is grammatical. However, in the past tense, you can't just use might for may in the utterance as May [something occur] is an exhortation to express a wish or a hope and is not a modal verb as in:
- He may arrive early tomorrow. [possibility] or
- He might arrive early tomorrow. [also possibility but less likely]
To express May God help me! in direct speech in the past, one would have to use something like:
"I was going through the most difficult moment of my life. I asked for God's help!". OR "Would that God had helped me."
may [verb] and might [verb] can be modals in the present referring to a future.
might can sometimes be used as a past tense of may in modal form.
may [something occur] can be a head word used to express hope or a wish (a formal usage). In this sense, there is no past tense for it and a workaround must be used.
In short, making may into might doesn't make it clear when the wish was made, and so you'll need an alternative strategy (like direct speech) to make your intent clear.
May is indeed used to wish
The usage of may you're asking about expresses a hope or wish while inverting may and the subject. The Oxford English Dictionary documents this usage in def. 12 of "may, v.1":
- Used (with inversion of verb and subject) in exclamatory expressions of wish (synonymous with the simple present subjunctive, which (exc. poetic and rhetorically) it has superseded).
All of the quoted examples of this usage use may and not might, e.g.,
1986 B. Gilroy Frangipani House vii. 30 May your soul never wander and may you find eternal peace.
Might was historically used to wish (with a present tense context)
You're wondering whether, nonetheless, one could treat might as an ordinary past tense version of may to represent a past wish. On its face, using might in this way is possible, but it runs into an issue - might could already represent a wish in the present. The OED classifies a wishing usage with might under definition 24:
- Used (since Middle English with inversion of verb and subject) in exclamatory expressions of wish (sometimes when the realization of the wish is thought hardly possible). poetic. Perhaps Obsolete.
1852 M. Arnold To Marguerite in Empedocles 97 Now round us spreads the watery plain—Oh might our marges meet again!
There is no sense of past tense in this particular usage of might, since the previous sentence is already in present tense.
Might is a lot less common for wishing today
Besides that, using might for wishing is a lot less common than using may in the same position. As an example when I did a search for "May_v God" in the Corpus of Contemporary American English, I had dozens of results that expressed a wish on the first page. For "Might_v God," I had one result in total, from the comments section (now scrubbed from the web, but documented in COCA's database) of an opinion piece in Washington Monthly:
You get the government you deserve.? Our forefather? s got good government. We? ve got Bush. In surrendering our rights and freedoms we are descending into cowardice and captivity. Might God help us, for we are not helping ourselves.
Again, might is used in a present tense context: we are descending. I conclude that might, when used to wish, doesn't have a strong temporal sense.
Might doesn't draw the neat temporal distinction you want
All of this helps explain how I initially read your usage. It felt odd, but I couldn't put my finger on it. I think it's because, when I read "Might God help me!" I don't read it as past tense. I read it as you - right now, narrating a past event - wishing for God to help either you or (in context) your past self. If it's you wishing this, I don't see the need for might to draw a distinction in tense.
Maybe another difficulty is a function of "May God help me!" being an interjection or exclamation; I'll read it as pertaining to whoever is immediately saying it whether you use may or might. If you really want to express someone's wish in a past situation, you could make it clear that someone in the past was saying or thinking this by using a reporting verb. For example:
I was going through the most difficult moment of my life. 'May God help me!' I thought.