The Office-Eucharist-Devotion Rule and the Trinity
Martin Thornton, in English Spirituality, explains how the Office-Eucharist-Devotion Rule, which underlies the Prayer Book, expresses our faith in the Trinity:
Acceptance of the transcendence of the Father, or in H.H. Farmer’s terms, of God as “ontologically and axiologically other”, is manifested in the objective offering of the daily Office of praise. The absolute demand made, and the perfect succour offered, by God the Son, form the basic ascetical attitude of worship in the Holy Eucharist. The immanental and rightly subjective religious element in personal devotion is inspired by the Holy Ghost conceived as indwelling Spirit: the Paraclete.
The Rule allows us to absorb this doctrine of God. Imbalance in any element of the Rule leads to an imbalance in our spiritual lives. Neglect of the Office (which teaches us about the Father’s transcendence) in favor of private prayer can lead to “subjectivism, sentimentality, pantheism, Quietism, and the like.” Neglect of personal devotion (which teaches us about the indwelling Spirit) in favor of the Office can lead to “legalism, formalism, and all the dangers of the Pharisees.”