The history of Cain and Abel.
The righteous suffer cruel persecutions in this world.
“Cain was followed by Abel, who was killed by his brother and served as the first prophetic symbol of the City of God which, like an alien on earth, was destined to suffer cruel persecutions at the hands of the wicked men who can properly be called natives of earth because they love this world as their home and find their happiness in the worldly felicity of the earthly city.”(4) -St. Augustine
Our Lord looks at our intentions and will.
“Our Lord does not recognize differences in appearance but takes account of intentions and rewards the will. God accepts our offerings not because he needs what we have to offer but because he wants our gratitude to be demonstrated through them as well.”(4) -St. John Chrysostom
Sin makes us a slave.
“Like a slave, Cain received a mark and he could not escape death. Thus is the sinner a slave to fear, a slave to desire, a slave to greed, a slave to lust, a slave to sin, a slave to anger. Though such a man appears to himself free, he is more a slave than if he were under tyrants.”(4) -St. Ambrose
The heavenly city is in exile on earth and the earthly city has its satisfaction in the world.
“Thus it is that the two series of generations that are kept so distinct, the one from Seth and the other from Cain, symbolize the two cities with which I am dealing in this work, the heavenly city in exile on earth and the earthly city, whose only search and satisfaction are for and in the joys of earth.”(4) -St. Augustine
