2 Corinthians. 8:7 NIV
But since you excel in everything— in faith IN SPEECH, in knowledge, in complete earnestness and in the love we have kindled in you—see that you also excel in this grace of giving.
The Bible has a lot to say about speech. Our mouths basically showcase what’s hidden in our hearts because the bible says that out of the abundance of the heart the mouth speaks. The process is pretty simple, what we fill our minds with, we eventually meditate on and the overflow of that becomes the word we speak.
For you and I to be excellent in speech, then, we must take care of what we think about.
Finally, believers, whatever is true, whatever is honorable and worthy of respect, whatever is right and confirmed by God’s word, whatever is pure and wholesome, whatever is lovely and brings peace, whatever is admirable and of good repute; if there is any excellence, if there is anything worthy of praise, think continually on these things [center your mind on them, and implant them in your heart].
When we spend our time thinking about what is mentioned in the above scripture, then our speech will be centered on the same things. As believers, our speech should reflect the word of God that we have believed. We cannot claim to have faith in God and yet what we speak is contrary to what his word says.
Life and death are in the power of the tongue, so the Bible says. With that in mind, we should use our speech to encourage and build up and not to discourage and tear down. We should use our speech to speak the truth in love.
Just as Paul admonished Timothy, we should be an example in speech by letting no unwholesome word proceed forth from our mouths, but only such word that are good for edification according to the need of the moment so that it will give grace to those who hear (Eph 4:29)
Remember, Jesus said that we will give an account for every idle word we speak.