Pro tanto quid retribuamus

Pro tanto quid retribuamus is the motto of the city of Belfast and also of HMS Belfast.  It comes from the Book of Psalms in the Latin Vulgate edition of the Bible - psalm 116 verse 12.  It means: "For so much, what shall we repay."

Cum sancto

Cum sancto sanctus eris, cum perverso perverteris is a wise proverb.   It means roughly - with the holy man you will be holy, with the wicked man you will be wicked.  Thanks to Laura Gibbs, on whose Bestiaria Latina Blog I found this proverb.  Laura attributes it to Polydorus, however a quick search on Google shows that it comes from 2 Samuel, chapter 22, verses 26 and 27, which in the Latin Vulgate reads:

26. cum sancto sanctus eris et cum robusto perfectus  
27. cum electo electus eris et cum perverso perverteris