Karma, is time passing while the spirit which is passing through many incarnations, continues to learn from one lifetime to the next, each continual lesson that is placed before them.
Like a clock, where each passing hour is another lifetime, and the speed of the clock being constant, so each spirit incarnation into another physical life f continues on it's ever progressive journey, taking off from previous lifetimes where they left off, finishes that lesson in the next physical life.
The lessons which have not been learned and the tests that God has placed before that spirit to pass must be mastered in the next lifetime until that spirit has become refined to the degree that their spirit vibration is pure enough so that they are prepared to travel up to higher spheres, and into the beginning of the Heavenly spheres, where without opposition from lucifer is no longer a threat, and each spirit can from this point grow to the degree of perfection that eventually returns them to a state of purity of spirit which allows that spirit to call themselves redeemed, and now returned to their original Heavenly home before their great fall with lucifer. so long ago.
Each planetary system is a microcosm and is a portion of a replica of the living space and part of the life forms of the higher realms. How better to learn how to think and act in those realms than to practice that form of perfection while in the physical universe. The Heavenly angels sent to this
This is the blockade of most people: they believe they are alone in the universe, that God does not know them and does not oversee everything that brings them forward from one struggle upward to a relief point of understanding and forgiveness, toward others and also for their own selves.
Love is the elevating power which draws the spirit upward to the Heavenly spheres. Harmony the guiding rudder of that ship which tunes the mind toward a form of thinking of how to think and how to act in preparation of