Perichoresis (from perikhōrēsis, "rotation") is a term referring to the relationship of the three persons of the triune God (Father, Son, and Holy Spirit) to one another. Circumincession is a Latin-derived term for the same concept. It was first used as a term in Christian theology, by the Church Fathers. The noun first appears in the writings of Maximus Confessor (d. 662) but the related verb perichoreo is found earlier in Gregory of Nazianzus (d. 389/90). Gregory used it to describe the relationship between the divine and human natures of Christ as did John of Damascus (d. 749), who also extended it to the "interpenetration" of the three persons of the Trinity, and it became a technical term for the latter. It has been given recent currency by such contemporary writers as Jürgen Moltmann, Miroslav Volf, John Zizioulas, Richard Rohr, and others. Modern authors extend the original usage as an analogy to cover other interpersonal relationships. The term "co(-)inherence" is sometimes used as a synonym. Etymology "Perichoresis" is derived from the Greek peri, "around" and chōreō, "to go, or come". As a compound word, it refers primarily to "going around" or "encompassing", conveying the idea of "two sides of the same coin". Suggested connections with Greek words for dancing ("choreia", spelled with the short letter omicron not the long omega) are not grounded in Greek etymology or early Christian use, but are modern in origin. The Latin equivalent circumincession comes from the Latin circum, "around" and incedere meaning "to go, to step, to march along", and was first by Burgundio of Pisa (d. 1194). The form "Circuminsessio" developed from the similarity in sound. Usage The relationship of the Triune God is intensified by the relationship of perichoresis. This indwelling expresses and realizes fellowship between the Father and the Son. It is intimacy. Jesus compares the oneness of this indwelling to the oneness of the fellowship of his church from this indwelling. "That they all may be one; as thou, Father, art in me, and I in thee, that they also may be one in us" (John 17:21). The great 12th century Cistercian reformer St. Bernard of Clairvaux spoke of the Holy Spirit as the kiss of God, the Holy Spirit being thus not generated but proceeding from the love of the Father and the Son through an act of their unified will. If, as is properly understood, the Father is