Lars wrote on his website that sibh may be used as a formal pronoun to refer to members of the clergy in the singular (though otherwise tú is always used in both formal and informal contexts):



Does anyone have any examples of this being used in native Irish?

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I'm an intermediate speaker of the Corca Dhuibhne dialect of Irish and also have knowledge on the old spelling
Soir gaċ síar, fé ḋeireaḋ thíar

I only found examples from Ulster.
Here a few of them:

Gcluin sibh sin, a shagairt? (Séamus Ó Grianna, Mo Dhá Róisín)
’Né sin an rud a dubhairt sibh, a shagairt? (ibd.)
Sé mur mbeatha, a shagairt. (Séamus Ó Grianna, Caisleáin Óir)
Nach gcaithfidh sibh a rá gurb é, a shagairt, nuair a chaith mé cúig bliana fichead i Meiriceá agus tháinig mé ar ais agus mé chomh bocht is a bhí mé an lá a d' imigh mé. (Séamus Ó Grianna, Gearrscéalta)
Le bhur dtoil, a shagairt,’ arsa Proinsias Bheagaide (Seosamh Mac Grianna, An Druma Mór)
A shagairt dhílis, arsa Andaí, a’s bhog an bheirt giota eile ar siubhal ar eagla go gcluinfidhe focal d’á gcomhrádh — a shagairt dhílis, tá sibh do mo sgannrughadh! (Seaghán Mac Meanman, Indé agus Indiu)

In most of these books, both tú and sibh occurs.

Thank you. Would it be fair to assume that this is particular to Ulster then? I would assume that, if so, that it came to be as an influence from Scottish Gaelic, in which sibh is used as a singular formal pronoun

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I'm an intermediate speaker of the Corca Dhuibhne dialect of Irish and also have knowledge on the old spelling
Soir gaċ síar, fé ḋeireaḋ thíar

Ceist mhaith.

Irish text corpora have large gaps.
I used Tobar na Gaedhilge which contains a lot of Ulster literature but much less of Munster and Connacht.
Nua-Chorpas na hÉireann also lacks much.
On the other hand:
My own searchable pdf files, e.g. many books by M. Ó Cadhain, yielded no results (i.e. always "tú").

There is nothing in Peadar Ua Laoghaire's extensive works that would suggest you can call a priest "sibh".

The book ‘A History of the Irish Language – from the Norman Invasion to Independence’ by Aidan Doyle gives one example of the apparent use of second-person plural forms that are semantically singular. It is from a letter written in 1561 by Seán Ó Néill (Shane O’Neill), Lord of Tyrone to Thomas Radclyffe, 3rd Earl of Sussex, and head of the English forces in Ireland. The letter was terse and was in protest at an English raid into O’Neill’s territory (which I think eventually resulted in all-out war). Here is an extract from the letter, as given in the book.

Beandacht ó Ua Néill docum an Iústís mar dhligheas sé agus dochum na coda ele don Chomhairle: agus atáim agá fhiarfaighe díobh créd do rinne mé do ní do rachadh a n-easonóir nó a ndíghbháil don Bhanríoghain nó dhaoibhsi as ar bhriseabhair orum gan fhátha gan ádhbhur, agus tairgsin gabháltus do dhénamh orum gan ghiolla gan liter do chur chugam ó do thángabhair a nÉrinn.

The letter contains second-person plural forms of prepositional pronouns and of verbs. It can possibly be argued that these are semantically plural, with the meaning ‘you and your associates’ but Doyle maintains that these are semantically singular. He says that the practice of addressing a stranger using the plural can be found in other letters written around this time but he doesn’t give any other examples. He goes on to state ‘It is clear that in the sixteenth century Irish was well on the way to developing a polite-familiar system like other languages did at this time’ but because of later social changes, where Irish was used less and less in formal situations, the polite form became unnecessary.

Thank you, Caoilte. This letter is very interesting. I haven't seen very many historical documents of such significance as this one written in Irish.

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I'm an intermediate speaker of the Corca Dhuibhne dialect of Irish and also have knowledge on the old spelling
Soir gaċ síar, fé ḋeireaḋ thíar

Little addition:
I've looked into Die Araner Mundart by Nikolaus Finck.

In its dictionary, there is: Cénas (Cionnas ~Cén nós) a bhfuil tú a athair easpog?
(in phonetic script, Irish orthography by me)
which he translates as: „Wie befinden sich Eure bischöfliche gnaden? Wie geht es Ihnen, hochwürdigster herr?“ - two very polite forms of addressing in German but no "sibh" in Irish.

In the grammar part, there is simply:
Eine besondere form für die höfliche anrede existiert nicht. (There is no specific form for a polite address.)