First learn to control their tongues

James 3:1-18
A perfect man: who is never fault in what he says, he is able to keep his whole body in check.
Tongue is a small part of the body, but it makes great boasts.
The tongue is a fire, a world of evil among the parts of the body. It corrupts the whole person, sets the whole course of his life on fire, and is itself set on fire by hell.
No man can tame the tongue.
With the tongue we praise our Lord and Father, and with it we curse men, who have been made in God's likeness. Out of the same mouth should not come praise and cursing.
Fig tree can not bear olives, grapevine can not bear figs.
Who is wise and understanding among you? Let him show it by his good life, by deeds done in the humility that comes from wisdom.
1)Wisdom comes from earthly, where have envy and selfish ambition, there you find disorder and every evil practice.
2)Wisdom comes from heaven is first of all pure; then peace-loving, considerate, submissive, full of mercy and good fruit, impartial and sincere.
Why?
Tongue connect to the heart, if a man's heart with evil mind, his mouth will come out with course and make his life worse.  It is contaminated by the earth.
Speak correctly is a wisdom and it comes from heaven, his life is influenced by the Lord.
Those who want to be teachers in the church must first learn to control their tongues.
Pure wisdom comes from God an shows itself in gentleness, peace, mercy. It is very different thing from being worldly-wise.
James offers a sort of counter-order wisdom, in contrast to the conventional wisdom of the wellborn and educated in the Greco-Roman world.
How?
May be I am foolish in these world, but I like to be wise man in present of the Lord, it is more effort to be done in my deed and learning in my life.
Don't curse or say any destructive or negative words to others. This is I need to do. If showing someone the correct way have to say with love.