I know this is one of Eaglesway favorite verses and as I dug deeper into this I saw a comparison between soul and spirit, joint and marrow and thoughts and intents
marrow is the key to understanding this, the word "marrow" (H4221) is defined as "fat" in the Old Testament and the word with the number H4221 is used only once throughout the entire Bible in Job.
Animal fat was used as grease in the past, so applying this to the three comparisons we can understand that; just as marrow is grease to a joint, helping it move easier with less hindrance or binding .....
So is the spirit to the soul, helping it move with less resistance, but is it a spirit of the world that helps the soul move easier away from God (into darkness) or His Spirit helping helping the soul to move easier towards God (into light)?
Just like a thought moves more easily with intent (motive/purpose/desire) ..... and again does a thought move easier with a motive/purpose/desire from the world or the motive/purpose/desire of God?
Seeing also that it goes from something spiritual (soul and spirit) to something physical (joint and marrow) back to something spiritual (thought and intent)
If we view the soul as mind and heart out of which comes all thought, desire, emotion and will ..... with the word "joint" we are talking about two things coming together to move as one to accomplish a task ..... and in the same way the mind and heart have to move as one, just like thought and intent/desire have to move as one
Just some thoughts
Good thinking
As you said, and its true, I do love that portion of scripture, and I see it as being very close to the core of all that God is doing in our lives and in the world. He says, "I am that I am"- and He is.... a pure, true, being of perfect love. He sees through us to the core of who we are, and He speaks to it, to us, where we really are. The things that happen in our lives are for this purpose, the good and the bad, the joy and the sorrow.We cannot get away from it because "all things are open to the eyes of the One with whom we have to do". He will open us up. Bring forth our true motives and secret intentions so that we can see who we are in the light of who He is- and grant us grace, as we see it, to change and be changed- into His likeness, so that there is no more shadow of turning and variableness as we become like Him, true, pure beings perfected in love. In my opinion this is the purpose of the lake of fire. Light so powerful it will penetrate every secret until every hidden thing s brought to light and all darkness consumed in the fire of His presence until every knee bows and all give glory to God before the irresistible beauty of Jesus, whose eyes are as flames of fire and whose face is like the sun shining in its strength.