The ISV renders the Greek word praiotes as “courtesy,” while other versions translate it as “meekness,” “gentleness” or “humility.” The ISV has taken some liberties, but it gives a sense, in today's English, of what Paul is saying. A humble attitude is necessary to show courtesy to others.
So, if the English “courtesy” is not literally in Titus 3:2, is it elsewhere? The Greek word philophron, which translates directly to the English “courtesy,” is used only once in the Bible. It comes from two other Greek words, philos, meaning “friend,” and phren, meaning “understanding,” “perceiving,” and “judging.” These two words indicating “understanding a friend” are put together to suggest the idea of courtesy.
Philophron appears in I Peter 3:8: “Finally, be ye all of one mind, having compassion one for another, love as brethren, be pitiful, be courteous” (King James Version). Many translations interpret philophron as “kind” or “humble,” and this is correct as well. Both Thayer's Greek Lexicon and Strong's Concordance define philophron as “friendly” and “kind,” but Strong's goes a little further, saying it can be summed up as the English word “courteous.”