Hebrew terms for Sin

 pesha', "offenses" (scelera), "iniquities" (iniquitates), or "crimes" (crimina), etc., has to do with the acts which are in themselves evil works and sins.

chata'ah, "sins" (peccatum), however, indicates the tinder of sin (fomes) which inclines toward these evil deeds and is the cause of them. Thus it is the tree of those fruits.

avon, "iniquity" (iniquitas) or "unrighteousness" (iniustitia), those good works which are done in the face of the sin that contends against us, especially if they are set up as righteousness. But they are not good works through the effort of the runner, but because of the indulgence of our merciful God. Thus in themselves they are iniquities and unrighteousnessess, that is, they are not righteous acts and do not suffice as equal to what is demanded.

resha', "ungodliness" (impietas). This is the very constitutinng principle of this kind of unrighteousness. It is a denial of sin, so that people do not confess sin and declare that good works are righteousness and abominate only offenses and crimes. Thus it comes about that they are righteous in the eyes of men and unrighteous before God.
(Luther's Works, Am. Ed., Vol. 25:277).

The distinction between pesha' and chata'ah is not always clearly drawn in Scripture. In Micah 1:5, they are synonyms. Resha is especially popular in Proverbs; about a third of all occurances of this word in the Bible are in Proverbs, and many are in Psalms as well. Proverbs 12:10, "Even the compassion of the wisked (resha', plural resha'im) is cruel!" The "iniquity" (avon) of the pagan nations is often spoen of: "The iniquity of the Amorite is not yet complete" (Gen. 15:16), and it is always a sin worthy of eternal damnation: "The Lord is about to come out of his place to punish those who inhabit the earth for their iniquity" (Isaiah 26:21).

Of course, for all sins there is a Savior: "God made him who had no sin to be sin for us, so that in him we might become the righteousness of God" (2 Cor. 5:21).