Cain and Abel were sons of Adam and Eve, the first humans according to the Bible. The Bible mentions a third son: Seth. Cain was a farmer, Abel a shepherd.
Related works of art:
Blake, William: Cain flees (1825)
Coxcie, Michiel: The Death of Abel (c. 1550)
Il Tintoretto: Cain and Abel (1550-53)
Lastman, Pieter: The Lamentation of Abel (1623)
Lievens, Jan: Cain kills Abel (c. 1640)
Lucas van Leyden: Adam and Eve Bemoaning the Death of Abel (1529)
Lucas van Leyden: Cain Kills Abel (1529)
Master Bertram: Cain and Abel bring offerings (1383)
Titian: Cain and Abel (1542-44)