I Worked Hard, Cain, I'm Not Showing Favor on Your Offering

In Hebrews 11, Cain and Abel both come to God with blood sacrifices. Both of them are seeking the favor of God; they're not atheist or sinning. But whenGod says he's not showing favor on Abel because of his faith, Cain goes absolutely ballistic. Why? Because I worked really hard and I'm entitled to the favor ofgod. And he got it. Therefore I'm going to kill him.