This chapter explains personhood as including not only individual substance, but having grounding outside of oneself, in relation. The Christian finds his grounding in Christ through communion. A Lutheran perspective on theosis is presented positively. However, it is clarified and elaborated by an explanation of simul iustus et peccator and the two natures in the Christian. In union with Christ, some of Christ’s qualities begin to characterize and shape the Christian’s new, regenerate nature, while the sinful nature persists and hampers the Christian until death. A Christian is one person with two natures, the sinful and the regenerate, while the regenerate nature lives in union with Christ sharing in, acting with, and growing by some of Christ’s qualities.