With Jesus being the author/source of salvation (Heb.5:9), it is only logical that his arch-enemy Satan be the author/source of sin. Satan, which means adversary, also known as the Devil (Rev.12:9). He is the one who has been sinning “from the beginning” (1 John 3:8). Jesus said Satan was a “liar and murderer” and was like this from the beginning (John 8:44). “In the beginning” coincides with the inception of creation (Gen.1:1).
Satan is some type of unholy angelic being. Paul spoke about how for the purposes to deceive the devil had transformed himself into an angel of light (2 Cor.11:14). This is an indictment that Satan is really a wicked angel of darkness (Eph.6:11-12), but an angel nonetheless. The fact God created everything (John 1:1-3; Col. 1:16), informs us of three things. One, Satan was created by God; two, he was originally good and holy for everything God made was “very good” (Gen.1:31); and three, the devil and his angels had the choice to do good or evil as we do. They chose evil/sin. See a definition of sin in these verses (Jas.4:17; 1 John 3:4; 5:17). Having sinned, the devil and his angels were driven from the holy presence of God (2 Pet.2:4; Jude 6).
God extends no forgiveness/redemption to the devil and his angels who know exactly where they are headed (Matt.8:28-29; 25:41,47). The devil has one goal in mind which is to deceive the world which lies under his influence (Rev.12:9; 1 John 2:15-17; 5:19). It is his desire to take the souls of mankind to hell with him. Remember what Jesus said to Peter, “Simon, Simon, behold, Satan hath desired to have you, that he may sift you as wheat” (Luke 22:31).
Satan orchestrated the first sin on earth (Gen.3:1-6; 2 Cor.11:3). He encouraged the greatest sin against Jesus (John 13:2,21-27; 18:1-5). Judas said, “…I have sinned in that I have betrayed innocent blood…” (Matt.27:3-4). He was responsible for the first sin in the church (Acts 5:1-4). Satan, “the tempter” (Matt.4:1,3), even tried to get Jesus to sin (4:3-11). If Satan had no regard for God’s Son, how do you think he views us? Anytime we are tempted to do wrong it is of the devil. “Let no man say when he is tempted, I am tempted of God: for God cannot be tempted with evil, neither tempteth he any man” (Jas.1:13). Remember the admonition, “Be sober, be vigilant; because your adversary the devil as a roaring lion, walketh about, seeking whom he may devour” (1 Pet.5:8). Have no doubt where sin begins. Satan will never stop. The only solution is to not ignorantly give him place/opportunity (Eph.4:27; 2 Cor.2:11). “Submit yourselves therefore to God. Resist the devil, and he will flee from you” (Jas.4:7; cf.1:13).