James 3v8-11
but no human being can tame the tongue. It is a restless evil, full of deadly poison. With it we bless our Lord and Father, and with it we curse people who are made in the likeness of God. From the same mouth come blessing and cursing. My brothers, these things ought not to be so. Does a spring pour forth from the same opening both fresh and salt water?

Our words can be deadly and often times defeat our testimony to the lost. We must pay close attention to the things we say taming our tongue, encouraging instead of scolding, praying instead hating. Let our words be filtered by the Spirit to plant seeds of faith and to water those in need; growing all things closer to the Father.

James 3v2
For we all stumble in many ways. And if anyone does not stumble in what he says, he is a perfect man, able also to bridle his whole body.