I was doing further reading in the writings of Allan Kardec (see original post) in The Spirits' Book, and I came upon some quotes which so eloquently refute the viewpoint of the "damnationists". I include it below:
1009. According to that, the penalties imposed on spirits are never eternal? "Interrogate your common sense, your reason, and ask yourself whether an eternal condemnation for a few moments of error would not be the negation of the goodness of God? What, in fact, is the duration of a human life, even though prolonged to a hundred years, in comparison with eternity? ETERNITY! Do you rightly comprehend the word? sufferings, tortures, without end, without hope, for a few faults! Does not your judgment reject such an idea? That the ancients should have seen, in the Master of the Universe, a terrible, jealous, vindictive God, is conceivable, for, in their ignorance, they attributed to the Divinity the passions of men; but such is not the God of the Christians, who places love, charity, pity, the forgetfulness of offences, in the foremost rank of virtues, and who could not lack the qualities which He has made it the duty of His creatures to possess. Is it not a contradiction to attribute to Him infinite love and infinite vengeance? You say that God's justice is infinite, transcending the limited understanding of mankind; but justice does not exclude kindness, and God would not be kind if He condemned the greater number of His creatures to horrible and unending punishment. Could He make it obligatory on His children to be just, if His own action towards them did not give them the most perfect standard of justice? And is it not the very sublimity of justice and of kindness to make the duration of punishment to depend on the efforts of the guilty one to amend, and to mete out the appropriate recompense, both for good and for evil, 'to each, according to his works'?"
There is much more where this came from.