- prayer (including oratio, meditation and contemplation);
- self-denial, including fasting, broadly called asceticism; and
- service to others, again broadly called almsgiving.
Whereas Christian doctrine generally maintains that God dwells in all Christians and that they can experience God directly through belief in Jesus, Christian mysticism aspires to apprehend spiritual truths inaccessible through intellectual means, typically by emulation of Christ. William Inge divides this scala perfectionis into three stages:
- the "purgative" or ascetic stage,
- the "illuminative" or contemplative stage, and
- the "unitive" stage, in which God may be beheld "face to face."
In his book "A History of Christian Thought From Its Judaic and Hellenistic Origins to Existentialism", Paul Tillich says this about Christian mysticism:
Mysticism is something that we find in Philo of Alexandria, for example. He developed a doctrine of ecstasy, (Greek: ek-statis) which means "standing outside oneself". This is the highest form of piety which lies beyond faith. This mysticism unites prophetic ecstacy with "enthusiasm", a word which comes from the Gree word en-theosmania, meaning "to possess the devine". From this there comes finally the fully developed mystical system of the Neo-Platonists, for example, of Dionysius the Areopagite. In this mystical system the ecstasy of the individual person leads to a union with the One, with the Absolute, with God.