The question was raised, “Where did Satan come from and when did he show up on the scene?”  This is my response…

• God created everything, the heavens and the earth; this includes the spirit realm (hosts of angels) – Gen 1:1
• He proclaimed that everything was good (Gen 1:31).  This would mean Satan wasn’t here yet.
• We see in 2 Peter 2:4 that God did not spare angels when they sinned, but cast them into hell and committed them to chains of gloomy darkness to be kept until the judgment and in Jude 6 the angels who did not stay within their own position of authority, but left their proper dwelling, he has kept in eternal chains under gloomy darkness until the judgment of the great day; there must have been some kind of rebellion against God from some of the angels.
• There may be more evidence of this rebellion from Isaiah 14:12-15  ¹² “How you are fallen from heaven, O Day Star, son of Dawn! How you are cut down to the ground, you who laid the nations low!  ¹³ You said in your heart, ‘I will ascend to heaven; above the stars of God I will set my throne on high; I will sit on the mount of assembly in the far reaches of the north;  ¹⁴ I will ascend above the heights of the clouds; I will make myself like the Most High.’  ¹⁵ But you are brought down to Sheol, to the far reaches of the pit.  It seems that Jesus is referring to this event in Luke 10:18   ¹⁸ And he said to them, “I saw Satan fall like lightning from heaven.
• I conclude that God, in his authority and justice, when confronted with the rebellion from Satan and other angels, cast them out of heaven and into hell and upon the earth.  This is where sin enters the world and Satan shows up on the scene, in Genesis 3.