Some food for thought inspired by various writings, e.g. Dallas Willard's
John Locke on spiritual and physical substance
From the viewpoint of substance in general, spiritual substances are at least as intelligible as material substances
A person, an individual = event: ‘located’ in time (they exhibit the usual temporal relations), but not in space (not above, next to, far from, etc. any other thing, and especially not those that have some such relations).
Life and natural development
Life of whatever kind has a natural development with a specific order. It can be deflected or stunted, but its natural course is set by the kind of life it is.
Life from above and its development
Analogous to natural life. Manifests itself as a gripping realization that Jesus really is the Anointed One, Christ, Lord. One who really understands who Jesus is sees their own situation in a realistic light and wants to take measures to remedy their condition by staying as close to Jesus as possible (discipleship).
I’ll take a bit of your blood, Jesus—enough to cover my debts—but I’ll not be staying close to you until I have to.
Staying as close to Jesus Christ as possible. - It is life with him, which from the reverse side is his life with us. As his disciples we are learning from Jesus how to live our life here and now in the kingdom of the heavens as he would live our life if he were we.
Obedience to Jesus Christ is not how we earn anything, it is simply the place where the kingdom of God is in relation to us. It is where we know it and where we know him. Merit is not the issue. Life is the issue: life beyond merit. - In contrast, a company in corporate America is a "meritocracy". Obedience to the company is how we earn everything. Merit is the issue, merit even if it costs my life.
Grace is God acting in our life to bring about, and to enable us to do, what we cannot do on our own (2 Tim. 2:1). Grace is an active agency in the psychological and biological reality of the disciple.
Discipline as "a means to grace"
Discipline in the spiritual life is doing something in our power that enables us to do what we cannot do by direct effort—because in this way we meet the action of God (grace) with us, and the outcome is humanly inexplicable. Grace points to God's action, but it doesn't point to my inaction. My contribution is well described as discipline. Grace is not opposed to effort but to earning.
The self is a substance, and its substance or "make up" consists primarily of intentional properties or states (specific "ofnesses" and "aboutnesses" of various kinds) in massive quantities, interwoven in characteristic ways to make up the life of one person. Spiritual substance in terms of intentional properties (Intentionality) and their interweavings.
Properties of events of a certain kind, which we usually think of as "mental". Intentional properties can be illustrated by someone e.g. seeing Charles crossing that street (=conscious event) ...this event having the property of being of or about Charles.