Genesis 4:1-3

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.