Cf:
A bird is known by his note and a man by his talk (Am., Br.). The bird is known by its note, and the man by his words (Br.). A bird is known by its song (Br.). Conversation makes the man (Br.). Speech is the index of the mind (Am., Br.). Speech is the picture of the mind (Br.). Tell an ox by his horns, but a man by his word (Am.). Your tongue is your ambassador (Am., Br.)
Русско-английский словарь пословиц и поговорок. Академик.ру. 2013.