Tao Te Ching, Chapter 56

Translation

56. 1. He who knows (the Tao) does not (care to) speak (about it); he who is (ever ready to) speak about it does not know it.

2. He (who knows it) will keep his mouth shut and close the portals (of his nostrils). He will blunt his sharp points and unravel the complications of things; he will attemper his brightness, and bring himself into agreement with the obscurity (of others). This is called 'the Mysterious Agreement.'

3. (Such an one) cannot be treated familiarly or distantly; he is beyond all consideration of profit or injury; of nobility or meanness:--he is the noblest man under heaven.

Practical Reading

Those who know do not speak; those who speak do not know. In knowledge, true understanding manifests in action, not explanation. What you truly know appears in how you live.