How do you build your spiritual body?

Paupers and criminals have everything to gain by the change from one world to the other. They have nothing to lose and they leave nothing behind to regret—it would be a happy release for most to be free from the necessity of supplying the needs of the body had they not to supply the needs of the spirit instead. Most of them have never given a thought to their spiritual welfare whilst on earth and they have to begin at the bottom of the ladder. Having lost their own material bodies, they use the bodies of others still in the flesh and incite the latter to all kinds of drunkenness and excess, so that they may gratify their own base desires. In our life, the principal aim is to supply the wants of the physical body, which helps to build up the spirit body within. In the spirit world, the principal object is to develop the soul that dwells in the spirit body, for the latter is not the spiritual man any more than our bodies are such.