Why was it such a sin, deserving of such punishment, not to cut the doves in two? The entire purpose of the providence of salvation is to separate good from evil in men and in the world, so as to destroy the evil and preserve the good, and eventually restore the purpose of creation. Therefore, that which is not divided in two remains belonging to Satan and leaves no part which God can claim. Accordingly, Abraham's offering was given to God externally, but internally it was given to Satan, and thus it became sinful.