Speech is the mirror of the mind.
(Imago Animi Sermo Est)

Nothing is more admirable than the fortitude with which millionaires tolerate the disadvantages of their wealth.

—Seneca

It is a great thing to know the season for speech and the season for silence.

—Seneca

You can tell the character of every man when you see how he receives praise.

—Seneca

Be not too hasty either with praise or blame; speak always as though you were giving evidence before the judgement-seat of the Gods.

—Seneca

Most powerful is he who has himself in his own power.

—Seneca

In anger we should refrain both from speech and action.

—Pythagoras

Speech is a mirror of the soul: as a man speaks, so is he.

—Publilius Syrus

Tears at times have all the weight of speech.

—Ovid

Do not fight verbosity with words: speech is given to all, intelligence to few.

—Moralia

Be a craftsman in speech that thou mayest be strong, for the strength of one is the tongue, and speech is mightier than all fighting.

—Maxims of Ptahhotep