Hi what a great forum. I am looking for a confirmation of a translation. Any help would be appreciated.

The phrase I need translated: Hold Fast in Life and Love

Is it: Coinnigh Diongbhailte sa Saol agus Gra

or is it: Coinnigh Go Tapa sa Saol agus Gra

Thank you so much in advance.

Coinnigh (hold) is a transitive verb, transitive only, in Irish. So you need something to hold.
The usual "something" is greim ("grip"), so coinnigh greim or coimeád greim (coimeád is another verb which can be used instead of coinnigh)
For "fast" use daingean or docht, so coimeád greim docht
Diongbháilte ("steadfast") isn't used in this context.
Tapa means "fast" only in the sense of "quick". So it cannot be used here.

Prepositions (here sa = in the) are usually used twice in Irish, so: sa saol agus sa ghrá.

So:

Coimeád greim docht sa saol agus sa ghrá.

(Don't omit the accents!)

Thank you so much Labhrás

Thank you for the confirmmation tiomluasocein