Before you speak, think if what you intend to say catches in one of the three sieves:
1. The sieve of truth
2. The sieve of love
3. The sieve of necessity

Think before you speak, think twice before you shout, think three times before you go mad.

Weigh every word before you speak it.

Thou weigh'st thy words before thou givest them breath.

Is it true? Is it kind? Does it need to be said?

First learn the meaning of what you say, and then speak.

Think twice before you speak, because your words and influence will plant the seed of either success or failure in the mind of another.

When you say something, make sure you have said it. The chances of your having said it are only fair.

The mouth should have three gatekeepers. Is it true? Is it kind? And is it necessary?

Before you speak, listen. Before you write, think. Before you spend, earn. Before you invest, investigate. Before you criticize, wait. Before you pray, forgive. Before you quit, try. Before you retire, save. Before you die, give. — WILLIAM A. WARD

Say what you think; think what you mean.

Think before you speak. Read before you think.

To speak and to speak well, are two things. A fool may talk, but a wise man speaks.

Before I speak, I have something important to say.