§ 34.7. =The Unity and Catholicity of the Church.=--The fact that Christianity was destined to be a religion for the world, which should embrace all peoples and tongues, and should permeate them all with one spirit and unite them under one heavenly head, rested upon the presupposition that the church was one and universal or catholic. The inward unity of the spirit demanded also a corresponding unity in manifestation. It is specially evident from the _Teaching of the XII. Apostles_ that the consciousness of the unity of the church had deeply rooted itself even in the Post-Apostolic Age (§ 20, 1). “The points which according to it prove the unity of Christendom are the following: firstly, the _disciplina_ in accordance with the ethical requirements of the Lord, secondly, baptism in the name of the Father, Son and Holy Spirit, thirdly, the order of fasting and prayer, especially the regular use of the Lord’s Prayer, and fourthly and lastly, the eucharist, _i.e._ the sacred meal in partaking of which the church gives thanks to God, the creator of all things, for the revelation imparted to it through Jesus, for faith and knowledge and immortality, and implores the fulfilment of its hope, the overthrow of this world, the coming again of Christ, and reception into the kingdom of God. He who has this doctrine and acts in accordance with it is a ‘Christian,’ belongs to ‘the saints,’ is a ‘brother,’ and ought to be received even as the Lord” (Harnack). The struggle against the Gnostics had the effect of transforming this primitive Christian idea of unity into a consciousness of the necessity of adopting a common doctrinal formula, which again this controversy rendered much more definite and precise, to which a concise popular expression was given in one common _Regula fidei_ (§ 35, 2), and by means of which the specific idea of catholicity was developed (§ 20, 2).--The misleading and dangerous thing about this construction and consolidation of one great Catholic church was that every deviation from external forms in the constitution and worship as well as erroneous doctrine, immorality and apostasy, was regarded as a departing from the one Catholic church, the body of Christ, and consequently, since not only the body was put upon the same level with the head, but even the garment of the body was identified with the body itself, as a separating from the communion of Christ, involving the loss of salvation and eternal blessedness. This notion received a powerful impulse during the 2nd century when the unity of the church was threatened by heresies, sects and divisions. It reached its consummation and won the _Magna Charta_ of its perfect enunciation in Cyprian’s book _De Unitate Ecclesiæ_. In the monarchical rank of the bishop of each church, as the representative of Christ, over the college of presbyters, as