I have 3 things I would like translated, if possible, to Irish Gaelic. They are:

1. May he who is deaf, blind and silent live a hundred years in peace.

2. Any man who appeals to the law against his fellow man is either a fool or a coward. Any man who cannot take care of himself without that law, is both. For a wounded man shall say to his assailant,"If I live, I will kill you. If I die, you are forgiven."

3. Slip of the tongue, slit of the throat.

for those who may be alarmed at the viciousness of my requested translations, please rest assured that they are song lyrics from one of my favorite bands, Lamb Of God.

I thank you in advance.

Nothing alarms us. That said . . .

1. Go maire an té atá bodhar, dall agus ina thost céad bliain i síocháin.

2. Aon fhear a dhéanann achomharc ar an dlí i gcoinne daoine eile, is amadán nó cladhaire é. Aon fhear nach féidir leis aire a thabhairt dó féin gan an dlí sin, is é an dá rud é. Mar déarfaidh fear gortaithe lena ionsaitheoir, "Má mhaireann mé, mairfidh mé thú. Má fhaigheann mé bás, maróidh mé thú."

3. Sciorradh teanga, gearradh scornaí.

Wait for more input, at least two more comments, corrections or other translations.

Thank you, you're awesome. I appreciate you!

Má mhairim, maróidh mé thú. Má fhaighim bás, maithfidh mé thú.

(the last means: "I will forgive you", maithfear thú means "You will be forgiven.")

You said: If I will live, I will live (to enjoy?) you. If I will die I will kill you.
The verbs mair (live), maraigh (kill), maith (forgive) shouldn't be mixed up though sounding similar.

Maireann mé / Faigheann mé - much better: mairim / faighim. (All dialects and Standard Irish use them.)

So ... how would I say "If I live, I will kill you. If I die you are forgiven." Not "If I live, I will kill you. If I die, you will be forgiven."?

Sorry, not trying to be a nag, or a pest, but definitely wanna make sure everything is right before I get some ink laid down.

Also, does 'sciorradh teanga' translate to 'slip tongue, slit throat? How would I add an 'of into the translation, or does that translate correctly?

Just use maithfear thú instead of maithfidh mé thú.

You don’t need "of" in Irish.

sciorradh teanga is a slip of tongue, verbatim.
Though traditionally sciorradh focail ("a slip of word") is used in Irish, sciorradh teanga is okay, esp. in comparison to throat.

Awesome. I apologize for lack of understanding when it comes to Gaelic. I've been using Duolingo, which is alright. They offer photos and word matching, spelling, but they don't have a tool to gauge your pronunciation, so I'm learning to spell, albeit slowly, learning new words, but there's not way to tell if I'm saying the word correctly. Not only do I want to learn the language for such trivial purposes as tattoo translation, but also to keep a part of my heritage alive to pass down to my children some day.