When we’re taught that we’ll be perfected in the hereafter, does that apply to all 3 glories or just Celestial?
The resurrection applies to all of mankind that ever lived on the earth, regardless of personal righteousness. So, everyone will be physically perfect no matter what kingdom they inherit. Here’s why.
There are two things that keep us separated from Heavenly Father; sin and death. The reason they do this is because they render us imperfect spiritually and physically. Sin renders us spiritually imperfect, and it does so through our own choices. Our sins are the fault of ourselves as individuals. Because of this, Jesus suffered the consequences for all our sins. That way, we won’t have to pay for our sins if we follow his word and his example as best we can.
Death renders us physically imperfect because our bodies are constantly dying and being replaced by new material. Eventually the body wears out and it can’t replenish itself fast enough. That’s the aging process (extreme Readers’ Digest version). At the end of our lives, our body is dying so fast it cannot keep itself alive, and we die. (of natural causes in this example)
Death came upon us because of what Adam and Eve had to do in order that we could be born. It’s not our fault personally that we die, but we still suffer the consequences of the decision Adam and Eve made. Because of this, Jesus was not only the first to be resurrected, but he also extended to all of us the gift of resurrection with a perfect body, no conditions or demands.