While it may not be obvious through a cursory look, Cain was likely the first human narcissist (Satan was the very first narcissist, see here). Let’s go through the Biblical evidence:
The first clue that Cain was a narcissist with insolent pride is found here:
“not as Cain, who was of the evil one and slew his brother. And for what reason did he slay him? Because his deeds were evil, and his brother’s were righteous.”I John 3:12
“You are of your father the devil, and you want to do the desires of your father. He was a murderer from the beginning, and does not stand in the truth because there is no truth in him. Whenever he speaks a lie, he speaks from his own nature, for he is a liar and the father of lies.”John 8:44
not as Cain, who was of the evil one and slew his brother. And for what reason did he slay him? Because his deeds were evil, and his brother’s were righteous.
but for Cain and for his offering He had no regard. So Cain became very angry and his countenance fell.Genesis 4:5.
If you do well, will not your countenance be lifted up? And if you do not do well, sin is crouching at the door; and its desire is for you, but you must master it.”Genesis 4:7.
Cain told Abel his brother. And it came about when they were in the field, that Cain rose up against Abel his brother and killed him. Genesis 4:8
Then the Lord said to Cain, “Where is Abel your brother?” And he said, “I do not know. Am I my brother’s keeper?”Genesis 4:9
.Cain said to the Lord, “My punishment is too great to bear! 14 Behold, You have driven me this day from the face of the ground (NOT true)
“and from Your face I will be hidden” (NOT true)
and I will be a vagrant and a wanderer on the earth, and whoever finds me will kill me.” (a grossly overstated fear)Genesis 4:13