What are some Renaissance words or sayings?
This is a very good question. As with languages today, vocabulary and idiomatic expressions will vary from country to country, city to city, maybe even neighborhood to neighborhood. I found for you a fantastic web site that lists Renaissance English vocabulary side by side with its modern equivalent. In some cases, it even gives the word's derivation. Here are a few of the entries:
anon = later = I will see you anon
e'en = even/evening = 'tis e'en, let us rest
fare-thee-well = good-bye
There are many more words and expressions on the web site www.schools.net.au (linked below).
Another site you might find interesting is Virtual Renaissance (linked below). It allows you to "experience" several aspects of life during the Renaissance
In what language?
If English, you have an advantage, because we can treat Shakespeare as a representative Renaissance writer, and dip into the many tallies of Shakespearean vocabulary out there. If you would like to include other English writers, there are electronic versions of Renaissance texts online, such as here: