It promotes “good” sins. Some lies are called “white lies.” Self-righteousness ranks sins.
What about pride, bitterness, unthankfulness, unhappiness, discontentment, gluttony, debate, envy, covetousness, hatred, variance, emulation, whispering, backbiting, implacable, unmerciful, foolish talking, jesting, etc.
Our deceitful hearts always justify our sins as “not so bad” and others’ sins as heinous.
It is like a cancer (II Tim 2:17). It is not content with one cell. It must grow and take more.
It is like yeast (Matt 16:5-12; I Cor 5:6-8; Gal 5:9). It affects the whole man and the whole congregation. You can’t limit it in its affects.
Sin deceives. Sin lies to its owner. Sin never tells you what is going to happen later.
Sin lied to Adam and Eve (Gen 3:6-7). The fruit appeared desirable in every way to them before eating it, but they instantly were naked in an empty world after eating it with the most horrible consequence to pay for themselves and every single descendent.
Sin lied to Amnon (II Sam 13:2,12-16). He was sick with desire for his beautiful sister Tamar, but he instantly hated and rejected her after ruining her in spite of her suggestion and willingness to be his wife and was dead just two years later.
Sin lied to Israel (Ezek 23:17). She thought she desired Babylon, but then hated him.
Sin lies to idolaters (Is 44:20). They cannot identify or evade the lie in their right hand.
We are to exhort one another daily against sin, because it is deceitful (Hebrews 3:13).
We must exercise – basic movements repeated often – unto godliness against sin (I Tim 4:7); we replace the presence and time of sin with basic things of godliness for spiritual growth.
Proverbs 4:23 is crucial. Start your discipline at the heart level. If you merely keep opportunity away, you will eventually burst forth into full blooming sin by the pent up demand of an unbridled heart. We cannot trust our own hearts (Proverbs 28:26; Romans 8:7).