(Gr. = “a statement of faith”). A theological formula drafted by Sergius, patriarch of Constantinople, and issued by Emperor Heraclius in 638. It forbade the mention or teaching of one or more principles of energy or modes of activity in the person of Christ, and it claimed that there was only one will in Him. Two councils held at Constantinople in 638 and 639 accepted the Ecthesis, but the Western Church did not. It was finally withdrawn by Emperor Constans II in 648. Eventually the church agreed that there were two wills in Christ, the divine and the human.

See also Monothelites.