The power of casting out devils, promised by our Lord Mark xvi. 17; Luke ix. 1; x. 17., and exercised by Apostles Acts v. 16; xvi. 18; xix. 12., and by Philip the Deacon and Evangelist Acts viii. 7., was long regarded in the early Church as a direct gift still bestowed by the Holy Ghost, apart from any human ordinance.  Justin Martyr Apologia I. §§ 6, 8; Tryph. lxxxv., Tertullian De Idolol. c. xi.; de Corona Mil. xi.; de Anima, lvii. de Spectac. xxvi.; de Præscript. Hæret. xli., Origen Contra Celsum, vii. c. 57., all speak of exorcism as being practised by laymen, even by soldiers, and women, by means of prayer and invocation of the name of Jesus.  Accordingly “an Exorcist is not ordained, for it is a gift of the spontaneous benevolence and grace of God through Christ by visitation of the Holy Ghost.  For he who has received the gift of healing is declared by revelation from God, the grace which is in him being manifest to all Const. Apost. viii. 26..”  When the extraordinary gift was found to have been withdrawn, exorcists are mentioned among the inferior officers of the Church, after readers and subdeacons Euseb. H. E. vi. 43; Syn. Antioch. in Encæniis, Can. 10:  Syn. Laod. Can. 24..  From an early period certain set formulæ, such as the Divine names, “The God of Abraham, and God of Isaac, and God of Jacob,” “The God of Israel,” “The God who drowned the king of Egypt and the Egyptians in the Red Sea,” were frequently invoked against demons and certain wicked persons Origen, Contra Cels. iv. c. 34 (p. 184)..