My Dear Brother,
I have nothing very especial on the points you speak of, save holding fast the great foundations that it is a new life communicated. “He that hath the Son hath life; he that hath not the Son of God hath not life;” only 2 Peter 1:4 is more conformity to the divine nature, as you say, though not merely attainment.
The word is the instrument as it is said, faith comes by hearing, ἀκοή, report, and hearing, ἀκοή by the word of God. It is hard to say how the word merely works, save that it is God's method of the revelation of Christ, and where accompanied by the quickening power of the Spirit, it becomes thus the means of life, what is spoken of as the word communicated to the soul by the Spirit becomes life.
In Paul's case it was sight, yet revealing His Son in him, indeed the words of Christ too came to his car. The Holy Ghost gave reality in his soul to that which his senses told him of. The written (or spoken word if true) is a revelation of that which is true of Christ, and of Christ Himself, so that while it is the divine power of the Spirit by which we are quickened, it is the revelation of Christ to the soul (which) is objectively that which quickens me, what the Spirit brings to my soul, so that it is faith, faith in the report, which is the outward means, while the thing contained in the word which is life, Christ. The word in itself is merely the outward means or instrument, and by itself, though all truth be in it, produces nothing (unless to leave us without excuse).
The incorruptible seed is clearly in contrast with corruptible, or nature. But as the living Word was the carpenter's son, without the work of God in the soul, so the revelation of truth, and Christ, and grace in the written word too. His words were the expression of Himself, and the Spirit of God has given us what is needed for salvation and blessing, and also revealed Him as in glory. Each make us responsible to receive them, but to have life-giving power, the Holy Ghost must reveal what is in them. It is a comparison or allusion to natural birth, but there is a divine nature communicated, a new life, Christ our life, brought spiritually into the soul by the operation of the Holy Ghost, with the word which reveals them. God reveals His Son in us, and so we have life, Christ our life, and so morally and intelligently, by the word which reveals Him. God begets us, though it be by the word, we are born of the Spirit, the Son quickens us, the Spirit is the immediate power as in all God's works, but He is pleased to do it by the revelation of Christ by the word. By the word in James, and in 1 Peter is either meant “by” as an instrument, or what is called the instrumental dative. It is of all importance to see that a new life is communicated, that Christ becomes our life, just as we had the life of Adam in the old man, the flesh.
Your affectionate brother in Christ,
J. N. D.