Albert Barnes Commentary Proverbs 11:13

"He that goeth about as a tale-bearer revealeth secrets; But he that is of a faithful spirit concealeth a matter." — Proverbs 11:13 (ASV)

A person who comes to us with tales about others will reveal our secrets also. Faithfulness is shown, not only in doing what a person has been commissioned to do, but in doing it quietly and without excessive talkativeness.