Eternal sin
In Catholic teaching there are six sins that blaspheme against the Holy Spirit. They are: Several passages in the Bible are frequently interpreted as referring to the unforgivable sin:
Christian views on sin
The first reference to "sin" as a noun is of ""sin" is crouching at your door; it desires to have you, but you must rule over it” waiting to be mastered by Cain, a form of literary theriomorphism. 
The first use of the verb is God appears to Abimelech "in the dream, “Yes, I know you did this with a clear conscience, and so I have kept you from "sinning" against me. That is why I did not let you touch her.”" in Genesis 20:3. Isaiah announced the consequences: "But your iniquities have separated you from your God; your sins have hidden his face from you, so that he will not hear. For your hands are stained with blood, your fingers with guilt. Your lips have spoken falsely, and your tongue mutters wicked things" — a separation between God and man, and unrequited worshipping.