Pride is the original sin. Remember Lucifer? Lucifer was the beautiful angel of heaven who defied the Creator and fell from grace as described in Ezekiel 28:17, which reads, "Your heart was proud because of your beauty. You corrupted your wisdom for the sake of your splendor."
The prophet Isaiah addresses Lucifer by saying, "How you are fallen from heaven, O Day Star, son of Dawn! … You said in your heart, ‘I will make myself like the Most High.’ But you are brought down to Sheol, to the far reaches of the pit."
Proverbs 16:18 describes the fate of Lucifer who became the devil, the serpent of old. “Pride goes before destruction, and a haughty spirit before a fall.”