Spirit
The umbrella entry for "Spirit" gathers only the Pauline material on the human spirit — what UPDV renders "the inward man." Larger ranges of related material — Holy Spirit, angels, demons, Satan, and the broader doctrine that man is a spirit — are catalogued under their own umbrella headings and are not duplicated here.
The Inward Man
The phrase appears in two places in UPDV. The first is Paul's account of his own divided experience under the law: "For I delight in the law of God after the inward man" (Ro 7:22). The point is local — there is something within Paul that consents to the law, even when his "members" do not — and it locates the consent at the level of the inward man rather than at the level of behavior.
The second is the Ephesian prayer, where the inward man is the place where the Spirit's strengthening lands: "that he would grant you⁺, according to the riches of his glory, that you⁺ may be strengthened with power through his Spirit in the inward man" (Eph 3:16). Here the human inward man is paired explicitly with the divine Spirit — the latter the agent of strengthening, the former the place where that strengthening takes effect.
Together the two passages mark the inward man as both the seat of consent to God's law and the site of the Spirit's empowering work.