The analogy is not limited to the productive medium. It extends to that which is produced, and also to the manner of production. The seed, which is planted in the earth, is a dead seed. So man's soul, when it is first cast into the soil of God's providence, is a dead seed. They are both alike dead, the material seed and the seed of immortality.
But neither the ground of nature nor that of providence, into which they are first received, would of itself alone reproduce them to a new life. To the natural seed, when planted in the earth, there must be applied the rain and the sunshine before it can be decomposed, incorporated with new elements, and vivified with new life and beauty. The earth, operating in connection with these exterior helps, takes off and removes the outer coats of the seed, until it reaches the central principle, which had been encrusted and shut out from all the benign influences of the sun and atmosphere, and with its fostering care rears it up from its embryo of existence to its developed and beautiful perfection. In like manner, when the seed of man's immortal spirit is planted in the midst of God's providences, it is not till the influences of the Holy Spirit are applied, that it is decomposed, if we may so express it, by a separation of the good and evil, and the eternal element, deprived of life by reason of sin, is made alive in the spiritual regeneration.
The analogy in the two cases is a very close one. The encircling system of providential arrangements, operating in connection with the aiding energy of God's Spirit, removes coat after coat of that selfishness which had enveloped and paralyzed every faculty; and reaching at last the central element of the soul, the principle of love, which had suffered this dreadful perversion, it restores it to that life, light, and beauty, from which it had wickedly fallen.
— A Treatise on Divine Union (1851) Part 6, Chapter 6.