Wedding prints
Ar scáth a chéile a mhaireas na daoine
We live in one another's shelter.
Quote the dictionary’s form when you want the older, archival flavour.
The wording is quoted exactly from the record and its cited source; personalisation touches only your own names and date, never the Irish.
About this saying
This is the shelter proverb as Ó Dónaill prints it, with the older relative verb ending (mhaireas) a survival from an earlier state of the language that dictionaries preserve. The form in general modern use, Ar scáth a chéile a mhaireann na daoine, has its own record. Both are real; the difference is register, like quoting the King James beside a modern translation.