First I'd like to ask if anyone knows if Mairtin O Cadahain is originally Gaelic-speaker (as a mother tongue) or he got it in early ages.

Now the translation request is:

"mar fuair "Cóilín s'acu féin, slán a bheas sé"...

"...cibé ar bith cé uaidh ar thug sé an ábhailleacht."

and the last one:

ba é an dá mhar a chéile é.


GO RAIBH MILLE MAITH AGAIBH!

Mairtín Ó Cadhain was born in Clochán Glas in Conamara when it was a strong gaeltacht; so the answer is very much yes.

mar fuair "Cóilín s'acu féin	Because their own Coilín got...
slán a bheas sé	may he be safe (a pious wish)
cibé ar bith cé uaidh ar thug sé an ábhailleacht	this one is tricky. I'll paraphrase. The phrase means "from whoever he inherited/obtained his michieviousness/playfulness"
ba é an dá mhar a chéile é	This is a stock phrase for "it didn't matter"

Yep, native speaker.

Reading "Idir Shúgradh agus Dáiríre", I take it?
Great stuff but not for the faint-hearted. I'd say "Cré na Cille" is actually easier, as far as the level of Irish in it goes.

...mar fuair "Cóilín s'acu féin, slán a bheas sé."
"...like "that Cóilín of theirs, safe may he be"* got.

...cibé ar bith cé uaidh ar thug sé an ábhailleacht.
"...wherever he'd got [inherited] the mischievousness from.

...ba é an dá mhar a chéile é.
...it was all the same.

* Slán a bheas sé, bail ó Dhia air, etc. are just polite things to say after mentioning someone's name or referencing him in a complimentary way. I don't know exactly why, but presumably it was supposed to ward off any harm that might otherwise be drawn to him as a result of being mentioned in public.
Anyway, it's still done in speech although not as much as it used to be. I'd associate it more with older speakers.

Oops! Ní fhaca mé an freagra thuas ó Aonghus, bail ó Dhia air.

quote:

it was supposed to ward off any harm

Exactly.

Glad to see we agree!

Is maith ann níos mó na tuairim amháin, go hairithe le duine cosúil le Ó Cadhain. Is fíor dhuit maidir le Cré na Cille; i bhfad níos simplí, ó tharla gur caint ar fad atá ann.

Agus mar go bhfuil an chaint chéanna sách athráiteach, déarfainn - ní gá dhuit dul ar tóir "scóllachán gránna" sa bhfoclóir ach aon uair amháin agus beidh sé agat go deireadh leabhair!

Dála an scéil, níl a fhios agam anois an bhfuil dul amú orm, ach bhí tuairim agam gurb as an gCnocán Ard don Chadhnach, in aice leis an Spidéal. Cá bhfuil an Clochán Ard?

Tá Cnocán Glas in aice leis an Spidéal. (Bhí botún sa mhéid a scríobh mé thuas)

go raibh mille maith agaibh, beirt.