Mystical theology

Mystical theology is a branch of Christian theology which focuses on experiences ("states of the soul") that are believed to have no physical or mental cause (i.e. "states" that are "mystical").

In Roman Catholic teaching, such states do not come about even with the ordinary aid of divine grace. Mystical theology, then, comprises among its subjects all extraordinary forms of prayer, the higher forms of contemplation in all their varieties or gradations, private revelations, visions, and the union growing out of these between God and the soul, known as the mystical union. As the science of all that is extraordinary in the relations between the Divinity and the human spirit, mystical theology is the complement of ascetical theology, which treats of Christian perfection and of its acquisition by the practice of virtue, particularly by the observance of the counsels.

What strictly comes within the province of mystical theology is the study of the processes of active and passive purification through which a soul must pass to reach the mystical union. Although the active processes are also treated to some extent in ascetical theology, they require special study inasmuch as they lead to contemplation. They comprise: purity of conscience, or aversion even to the slightest sin; purity of heart, the heart being taken as the symbol of the affections, which to be pure must be free of attachments to anything that does not lead to God; purity of the spirit, i. e. of the imagination and memory; and purity of action. It is to these processes that the well-known term "night" is applied by Discalced Carmelite reformer St. John of the Cross, since they imply three things which are as night to the soul in so far as they are beyond or contrary to its own lights, viz., the privation of pleasure, faith as substituted for human knowledge, and God as incomprehensible, or darkness, to the unaided soul. Passive purifications are the trials encountered by souls in preparation for contemplation, known as desolation, or dryness, and weariness. As they proceed sometimes from God and sometimes may be produced by the Evil Spirit, rules for the discernment of spirits are set down to enable directors to determine their source and to apply proper means of relief, especially should it happen that the action of the Evil One tends to possession or obsession.

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