Aiming toward living a life in faith is nothing more than releasing fear, and allowing that which is to be, to be. When we are going against our true nature, when we see ourselves separate from other-selves, when we see some people as “worthy” or “unworthy” of our love, acceptance or whatever other form love takes, it is simply nothing more than separation: fragmentation of myself.
Your “densities” are basically groupings of levels of complexity. The third density, which we together enjoy at this time, is the first density of self-aware entities, and its denizens begin to seek the lessons of love by making the initial choice as to their path or style of seeking and realizing that love. 3d = To know good and evil and then to die.
We have a harvest of lessons learned and unlearned at the end of a lifetime. Between incarnations, we look at that harvest, and plan our next lifetime, in its broad strokes. We build on what we feel we have learned, and place relationships and circumstances in our way that we wish to work upon further. When we enter the birth process, we forget all that we have planned, and the darkness of Earth consciousness descends. In that dim light, we work all our lives, again attempting to learn our lessons of love, again working on difficult relationships and challenging issues that span many incarnations.