What is the indwelling of the Holy Spirit?

While on earth, you manufacture certain textures for the soul, its dress, which correspond in every particular with the characteristics of someone of the spirit spheres. 

It is difficult to explain how the acts of life affect the texture of the indwelling spirit, but it is on the same principle, as that which modifies the physical organisation of the unborn infant, and as impressions made on the mother's mind can change the characteristics of her angel child, so can selfish, miserly acts, intensified by hate and remorseless feelings, eradicate from the indwelling spirit nearly every bright, beautiful spot upon it. 

Every act in life has a well-defined effect on the spirit.

―Lucretus in Spirit