There is infinite variety, and no one thing can be identical to any other thing. There is an infinite variety in the heavens as well. The variations in the heavens are variations of goodness, and they are the basis of all differentiations there. These variations are defined by the truths (which are manifold) that shape the goodness of a given individual. That is how all the angelic communities in the heavens and all the individual angels in the communities are differentiated from each other. They still act as one because of the love they receive from the Lord and because of their devotion to a single purpose.
In general terms, goodness and truth are differentiated by level into earthly, spiritual, and heavenly varieties. Broadly, the three levels of goodness and of accompanying truth match the three heavens. There are three levels of goodness and truth in the inner self and three levels in the outer self as well. There is earthly goodness, civic goodness, and moral goodness. The earthly kind of goodness into which some of us are born is not good in the other life unless it becomes spiritual goodness. On earthly goodness that is spiritual and earthly goodness that is not spiritual. There is intellectual truth and there is factual truth.
from New Jerusalem, Section 26