Rules - 2:2

2.  If you desire to be cheerful among honest friends, take care that your joy be not contrary to Christian love, nor to purity & respectability.  Refrain therefore from rude insults & mockery that respectable people would be ashamed to hear.  First, because such lewd words are an open testimony of an impure heart.  "For out of the abundance of the heart the mouth speaketh" (Matthew 12:34).  Secondly, smutty jokes & foul speech smooth the road to shameful conduct.  


Indeed, you may say, "One has to have something to relate when in company with his friends to pass the time & delight each other."


This is a wretched excuse.  First of all, such mirth is clearly forbidden in God's Word.  "Neither filthiness, nor foolish talking, nor jesting, which are not fitting," says the holy Apostle Paul - we must avoid them.  Secondly, such lewd speech provokes the wrath of God (Ephesians 5:4, 6).  Through suchlike evil talk & vain mirth the Holy Spirit is grieved (Ephesians 4:29, 30).


The tongue is the glory of man & the crown of all the members of the body.  Shall a person then use it for obscenity?  When the tongue is corrupt it defileth the whole body, filling it with unrighteousness (James 3:6).  For this reason, loathe every kind of filthiness & let your speech be always pleasant & upbuilding, so that those who hear it may be bettered thereby.  Use your tongue to admonish the sluggard, to instruct the ignorant, & to comfort the sorrowing.  God will increase his gracious gifts to you accordingly (Mark 4:25).

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