Actually, there is a bible verse Proverbs 17:28, so that probably counts as the first mention of something similar. I always thought it was Mark Twain. It sounds so much like him. But researching it led only to this quote of Benjamin Franklin: Silence - Speak not but what might benefit yourself or others. Avoid trifling conversation. Not exactly the same thing. In many other places the quote is attributed to Lincoln. But it is also attributed to Maurice Switzer and Dr Arthur Burns! The most common attribution though is to Lincoln.