According to the Eastern Orthodox doctrine of deification, we can have communion with God in the divine life. That is, mere humans can become immortal and incorruptible. In addition, through deification humans share the moral attributes with God including righteousness or goodness, holiness, love and mercy. Thus, these are the attributes of the divine nature that we share and that supposedly justifies the assertion that we share the divine nature, become deified and become gods. There is more to it — including the notion that the divine life enters into us to take up habitation and we share a healed life in Christ.
The problem with this kind of assertion in the creedal tradition that accepts creation ex nihilo is that we cannot reasonably be thought to possess these or any attributes in a divine way. In the tradition, God is not good in the same sense that humans could possibly be good, for God cannot fail to be good. In fact, many theologians maintain that God is the very source and standard of goodness. If God cannot fail to be good, then he has no moral duties because he does not stand under a moral law that could bind him. Even if we take a watered down version of divine goodness and merely hold that God is perfectly good and so cannot do anything evil, we must wonder in what sense God is good that is like human goodness. Humans are morally good because they abide a moral law and do good works. If God cannot possibly do anything evil, then God is not good in this way and saying that â€œGod is goodâ€ means something quite different than saying that â€œthis man is goodâ€. So divine goodness is not really comparable to human goodness at all. It is an abuse of language to suggest that humans have the same kind of ethical or moral property of goodness as God because in the conventional tradition of the creeds, God has no moral or ethical goodness at all. Thus, comparing human goodness or holiness or love to divine goodness fails to observe the ontological and qualitative differences between Godâ€™s mode of being good and human modes of being good and evil.
On the other hand, we can participate or share the omni-attributes with God in exactly the same attenuated sense as Godâ€™s moral attributes. Certainly humans possess some power, though not all power. We can be wise and have knowledge, though we cannot possess all wisdom or all knowledge as God does. We can increase our influence and power beyond our immediate physical presence through instruments and have at least some sense of presence in the world, though admittedly not omnipresence. We can exercise power and knowledge but in human proportion and in a way fitting for humans. It is exactly the same with human goodness. We can only be good in a way that is possible for humans. Yet there is an ontological and qualitative difference between the way that humans can exercise power and have knowledge in comparison to God.
The truth is that we cannot possess any of the attributes of the divine kind if we are essentially created ex nihilo. I may possess goodness, power and knowledge, but in a human rather than a divine way. These are therefore human properties rather than divine properties. Further, it isnâ€™t possible for the created human way of having these properties to be transformed into the uncreated and self-sufficient way in which God has them. If a thing is created, this past fact is an essential fact about it that cannot be changed even by divine power. Not even God can create an uncreated thing. Thus, comparing the human way of having properties like righteousness, knowledge and power to the divine mode amounts to a logical category mistake.
What the doctrine of deification gives, the doctrine of creatio ex nihilo takes away. Thus, what LDS mean by deification will always be different than what those in the tradition mean by theosis or deification. However, I doubt that they can truly mean anything like that we truly become divine or share any divine attributes. But with that admission, the entire notion of deification seems to me to be eviscerated.