4:2. And again she brought forth his brother Abel. And Abel was a
shepherd, and Cain a husbandman.

4:3. And it came to pass after many days, that Cain offered, of the
fruits of the earth, gifts to the Lord.

4:4. Abel also offered of the firstlings of his flock, and of their fat:
and the Lord had respect to Abel, and to his offerings.

Had respect... That is, shewed his acceptance of his sacrifice (as
coming from a heart full of devotion): and that, as we may suppose, by
some visible token, such as sending fire from heaven upon his offerings.

4:5. But to Cain and his offerings he had no respect: and Cain was
exceeding angry, and his countenance fell.

4:6. And the Lord said to him: Why art thou angry? and why is thy
countenance fallen?

4:7. If thou do well, shalt thou not receive? but if ill, shall not sin
forthwith be present at the door? but the lust thereof shall be under
thee, and thou shalt have dominion over it.

4:8. And Cain said to Abel his brother: Let us go forth abroad. And when
they were in the field, Cain rose up against his brother Abel, and slew
him.

4:9. And the Lord said to Cain: Where is thy brother Abel? And he
answered: I know not: am I my brother's keeper?