I know that we can let our guard down and get carried away amongst friends, but we should strive to maintain dignity and poise as it behooves us. When someone addresses me abusively I feel they don't respect me or are treating me like they don't think I have feelings. When we are intimate we are to be sensitive also and know our boundaries respecting others.
Is there a time and place for vulgar lingo? I, personally, evade dubious expressions and words to be on the safe side, because I believe in maintaining dignity, respect, and testimony. Our manner of speech should be beyond reproach and blame if we desire to be an elder or a deacon. There is such an animal as appropriateness and just between guys on a fishing trip, for example, the language might become less restrained and more informal. But we never stoop to the level of the lowest common denominator if we are in bad company. I still take umbrage at certain four-letter words even though I've been in the military and don't expect to hear this from Christians, even though I have heard it from the horse's mouth. Are we trying for shock value sometimes or to make a point? Is it an aberration or customary usage?
Our verbiage should be clean and uncorrupted, but that is open to interpretation and other factors. Sometimes it just doesn't become one to stoop to such a level when he should know better, and better is expected of him or her. Certain words should be a no-no and clearly verboten, so to speak; I will not delineate which ones. Our tongue gives our mind away and is a telltale sign of what we are thinking. Indiscriminate usage is out of line and also the free and easy overuse of expletives to drive home a point. Educated people should have refined language; it is expected of them.
There are four verses to consider: Eph. 4:29; Col. 4:6; and Psa. 19:14. The latter says: "Let the words of my mouth and the meditations of my heart be acceptable in thy sight, Oh LORD." What exactly is corrupt communication is open to debate and one must judge for himself? Note well that our liberty is curtailed and limited by our brother's conscience--we can't be reckless or careless by any means. If ever I use a word to make a point I make it clear that I do not approve of its usage and be apologetic; however, there are words that are a no-no at any time, under any circumstance if one claims to be a follower of Christ. Soli Deo Gloria!