 Some ancient Christians, most 17th-19th century unitarians, present-day “biblical unitarians”, and some modern subordinationists such as the Jehovah’s Witnesses hold the Holy Spirit to be a mode of God—God’s power, presence, or action in the world. (See the supplementary document on  unitarianism.)  Not implying modalism about the Son, this position is harder to refute on New Testament grounds, although mainstream theologians and some subordinationist unitarians reject it as inconsistent with New Testament language from which we should infer that the Holy Spirit is a self (Clarke 1738, 147). Modalists about the Spirit counter with other biblical language which suggests that the “Spirit of God” or “Holy Spirit” refers to either God himself, a mode of God (e.g., his power), or an effect of a mode of God (e.g., supernatural human abilities such as healing). (See Burnap 1845, 226–52; Lardner 1793, 79–174; Wilson 1846, 325–32.) This exegetical dispute is difficult, as all natural languages allow persons to be described in mode-terms (“Hillary is Bill’s strength.”) and modes to be described in language which literally applies only to persons. (“God’s wisdom told him not to create beer-sap trees.”)