PURITY OF HEART
There is a difference in saying something that comes across as unkind or unclean and saying something intentionally that is unkind or unclean because it was the disposition of the heart.
Christians, even vigilant Christians, are able to go for a while without their inner corruption rising up and spewing out, but until they die to self and surrender completely to the purifying work of the Holy Spirit, they will be plagued from time to time with unkind or an unclean urge.
Satan, sinning religion, and society wants us to believe that such leanings are normal because "we are only human" or because we have not matured.
Actually the problem comes from the sinful nature, rather than the human nature. Therefore "being human" is just an excuse for a sinful urge. Also, the problem is not because we lack maturity but because we lack purity.
This is where the lie of "progressive sanctification" rears its ugly head. Christians acknowledge that there is a spiritual cleansing and renewing at the time of conversion, and they will also acknowledge that there is a life long growth in grace that takes place after conversion, but they often deny the very truth that they need to accept. There is an entire sanctification that delivers Christians from the uncontrolled inward tyranny that rises up from time to time. This attitude of resistance is the Old Man, the carnal mind, the evil heart of unbelief. It is not just an inconvenience or a disturbance, it is a corruption, which cannot be subjugated, and it will lead a Christian away from God.
When those moments of un-Christian attitude eruptions pollute your thoughts, desires, conversation and actions, remember, God can and will deliver you, if you come to Him by faith.
1 Thessalonians 4:7
7 For God hath not called us unto uncleanness, but unto holiness.
1 Thessalonians 5:23-24
23 And the very God of peace sanctify you wholly; and I pray God your whole spirit and soul and body be preserved blameless unto the coming of our Lord Jesus Christ.
24 Faithful is he that calleth you, who also will do it.
Hebrews 12:14-15
14 Follow peace with all men, and holiness, without which no man shall see the Lord:
15 Looking diligently lest any man fail of the grace of God; lest any root of bitterness springing up trouble you, and thereby many be defiled;
1 John 3:2-3
2 Beloved, now are we the sons of God, and it doth not yet appear what we shall be: but we know that, when he shall appear, we shall be like him; for we shall see him as he is.
3 And every man that hath this hope in him purifieth himself, even as he is pure.