Genesis 4:1-5

Now the man Adam knew Eve as his wife, and she conceived and gave birth to Cain, and she said, “I have obtained a man (baby boy, son) with the help of the LORD.” And [later] she gave birth to his brother Abel. Now Abel kept the flocks [of sheep and goats], but Cain cultivated the ground. And in the course of time Cain brought to the LORD an offering of the fruit of the ground. But Abel brought [an offering of] the [finest] firstborn of his flock and the fat portions. And the LORD had respect (regard) for Abel and for his offering; [Heb 11:4] but for Cain and his offering He had no respect. So Cain became extremely angry (indignant), and he looked annoyed and hostile.