Inscription appears twice: on the abacus and in the upper part of the scene.
Left side: a bearded figure (Cain) cultivates the land, and oxen walk in front of him. Main side: Abel and Cain present their offerings: a lamb for the first, and a sheaf for the second. Above, we can see the hand of God, two fingers pointing towards Abel. Right side: Cain holds his brother by the hair and raises an axe in his right hand.
Reference
:
Capitals 1 to 5 follow a narrative order.
Pérez de Urbel, J. Et W. M. Whitehill (1931). « La iglesia románica de San Quirce », Boletín de la Real Academia de la Historia, Tome 98, p. 795-812.
García Morilla, Alejandro (2015). Corpus Inscriptionum Hispaniae Medievalium. Burgos (siglos VIII-XIII), Vol.1, Universidad de León, Servicio de Publicaciones, p. 121-122.