"Trinitarian Ecclesiology is an example of this approach to the mystery of the Church that places the divine missions at the head and the heart of the work. The order of Journet’s work is based on the four causes of the Church. Journet situates the treatise on the hierarchy in its proper place as belonging to the efficient cause of the Church in order to treat the more central mystery of the Church in her formal and material causes, namely the sanctifying gift of fully Christic charity and its visible manifestation"--