Ephesians 5:4 Let there be no filthiness nor foolish talk nor crude joking, which are out of place, but instead let there be thanksgiving.
Proverbs 12:23 A prudent man conceals knowledge, but the heart of fools proclaims folly.
Proverbs 15:2 The tongue of the wise commends knowledge, but the mouths of fools pour out folly.
Jude 1:10 But these people blaspheme all that they do not understand, and they are destroyed by all that they, like unreasoning animals, understand instinctively
Colossians 3:8 But now you must put them all away: anger, wrath, malice, slander, and obscene talk from your mouth.
Matthew 12:34-37 You brood of vipers! How can you speak good, when you are evil? For out of the abundance of the heart the mouth speaks. The good person out of his good treasure brings forth good, and the evil person out of his evil treasure brings forth evil. I tell you, on the day of judgment people will give account for every careless word they speak, for by your words you will be justified, and by your words you will be condemned.”
Romans 1:28 And since they did not see fit to acknowledge God, God gave them up to a debased mind to do what ought not to be done.
Paul’s appeal to the Ephesians was to be ever mindful of who they were in Christ and as such there ought to be a difference in how they speak and act even if the rest of the culture approves. They ought to know what is right, pure, and God honoring in their speech and actions. They ought to weigh every word in the light of God-honoring speech. As men, don’t have to spend much time outside our homes before we are bombarded with course language, filthy jokes, or other meaningless talk that adds nothing of value to our soul and certainly not toward God. We need to recognize and be able to discern what is right, honorable, and pleasing to God. The problem is we don’t recognize it as wrong or we shrug it off as fitting in. This problem has many roots that are anchored to our heart, mind, and soul. Neglect, complacency, remaining an infant in things of God, busyness, a lack of desire to honor and glorify God, wanting to fit in, shallow and stagnate knowledge of God’s Word, no hunger or thirst for His leading, and unwilling to fully commit to the will of God.
Psalms says: Understand, O dullest of the people! Fools, when will you be wise? He who planted the ear, does he not hear? He who formed the eye, does he not see? He who disciplines the nations, does he not rebuke? He who teaches man knowledge— the LORD—knows the thoughts of man