If you know someone with a perverted mouth - it is because it flows from a morally bankrupt mind. Even as I reread this statement, something within me just recoils from such a strong statement as this - and yet - when we truly understand what God is saying here in Proverbs - that is exactly what is being communicated.
The first thing we see here is a man with a "crooked mind." The word for "crooked" is the Hebrew word "iqqesh" and it means to be perverse, twisted, and crooked. The idea is that of someone who has a moral, religous, and social perversion by which their mind works. They do not think thoughts that are aligned with decent morals. They despise not just morals - but also religion and any kind of social contract by which men seek to live together in a decent fashion. They highly despise the idea of morals that are the result of religious principle. They hate such things - seeing themselves as free moral agents to determine whatever morals or lack of them they want. The consequences of such moral mental suicide is that they cannot find any good. This really is not that shocking since they would deny the existance of any kind of universal good or absolute truth. To them truth is relative to the situation - and since they hate moral goodness - it is not difficult to see that they revel in the evil and the godless things of the world - and tend to shy away from anything else. Thus - of course they would reject the good - and not be able to find any in society.
The second thing we see is a man who is perverted in his language. Perverted language is language that seeks to throw down, overturn, destroy, and wander from accepted biblical norms of how we should speak. There is a lot of disagreement on what this means in today's society. We've slowly grown to be the first society historically in the church to embrace cursing from the pulpit. The excuse that is so often used is that of saying that words are just words - we are the ones that make them curse words - or at least bad ones. What I find a little disingenuous about all this is that even the world system used to have a set of words that they would not allow on television and movies. It has only been over the past couple of generations that these accepted norms have been overturned in favor of the current "delightful" fare that we've embraced in our day. As you can tell, I am of the opinion that such language is totally unacceptable not just for use in the pulpit - but for use in every day life. It seems to me that as our society has retreated from God - we've also retreated from being circumspect about the things we say. To confess my own sins - I've watched my own speech begin to be down-graded, if you will. The Holy Spirit is in the process of encouraging (and often rebuking) me as He seeks to have me live above the moral cesspool of the accepted speech of my society.
The danger here is that we are warned that such speech DOES come from a mind that is being twisted away from the truth. The other danger is that when we do this we are warned that we "fall into evil." Whenever the church thinks it can reach the world by aping the world's behavior - we watch the opposite happen. First, we do not reach the world - but oh, how the world "reaches" us. We watch the same value systems - which might better be called "value-less" systems - that are in the world truly invade the church. When we do not watch our mouths - we will allow a kind of reverse-infection to occur in our hearts. The word used for mind in the first part of this verse actually means, "heart." Therefore when we do not watch our mouths - it is evidence that our hearts have been captured as well.
Jesus said that out of the abundance of the heart the mouth speaks. Therefore is it too strident a thing to say that if we have a perverse mouth - it arises out of a twisted and deceived mind? Our mouths simply reveal what is in our hearts. It would be to our benefit to watch our mouths and be careful what is allowed to come forth from them. In the end - we might look more "appetizing" the world if we do - but could that be simply because we lose the distinction of speaking in a holy manner that embraces purity and righteousness.
Let me say one last thing though - unless some get the idea that I think we are to be the public censure of all that is unacceptable speech-wise. We are called to be salt and light. That means we embrace holiness - not as a means of beating the lost to death - but as a means to be different and to be a thirst-creator in our world. The lost WILL become thirsty for what we ARE - and therefore will want the One who has changed us. Our purpose is to allow holiness to be revealed in our lives as a thirst-agent. We are not to use holiness as something to shame the lost into feigned obedience to God. That will do more to harm the gospel than reveal it. So . . . my admonition to you from Scripture is to have a mouth that is radically different than the world. Let your mouth not be filled with perversion - and your heart filled with deception and twisted morals. Instead let it be filled with Your Lord - who, by the way, did not descend into such language anywhwere in the gospels. He simply lived for God - spoke for Him - and although rejected by some - was embraced by many who saw His actions - His words - and His heart - and became incredibly thirsty for real holiness. May God make us those same things in our generation.