As originally published in March 1550, the Ordinal of the Book of Common Prayer prescribed, in the ceremony of ordination of a priest, the following interrogatory and response:
The Bishop.Will you then give your faithful diligence always so to minister the Doctrine and Sacraments, and the Discipline of CHRIST, as the LORD hath commanded, and as this Church and Realm hath received the same, according to the commandments of GOD; so that you may teach the people committed to your Cure and Charge with all diligence to keep and observe the same?Answer.I will do so, by the help of the LORD.
As so written (probably by Archbishop Cranmer), the question formed part of the ordination ceremony called the "Exhortation", in which the Bishop "called out" the ordinand to undertake the special responsibilities of a life in the priesthood. That interrogatory and response continued in the same words in all subsequent editions of the Book of Common Prayer, including those adopted by the Protestant Episcopal Church (USA), down through the 1928 Edition. (The American version dropped only the words "and Realm".)
As a completely separate and different kind of undertaking, all English clergy were required to subscribe, before entering into office, an oath of allegiance to the Crown, the Thirty-Nine Articles, and an "Oath of Canonical Obedience". This was done separately, apart from the service of ordination. The 1913 Prayer Book Dictionary explains the latter oath as follows:
The earliest form of the Oath was the solemn declaration of a bishop after consecration to obey and maintain the "Sacred Canons" of the Church. It was not a promise of obedience to a person; and, though eventually it took a personal form, the meaning and scope was not thereby changed. . . The obedience promised is therefore limited to what is prescribed by the law and custom of the Church. This was very clearly stated by the Judicial Committee of the Privy Council in the case of Long v. The Bishop of Capetown (Broderick and Fremantle 313): "The Oath of Canonical Obedience does not mean that the clergyman will obey all the commands of the Bishop against which there is no law, but that he will obey all such commands as the Bishop is by law authorised to impose"; that indeed is what is signified by the qualifying word "Canonical". . . .The form of the Oath of Canonical Obedience as taken by a priest or deacon is: "I, [name], do swear that I will pay true and Canonical obedience to the Lord Bishop of A. and his successors in all things lawful and honest. So help me God."
When the newly formed Protestant Episcopal Church (USA) split off from the Church of England and adopted a Constitution in 1789, the Oath of Canonical Obedience was carried over in the following form, required to be subscribed by each new ordinand (which, since it did not invoke the Deity as witness, was not literally an "oath", but rather a "declaration"):
. . . I do solemnly engage to conform to the doctrines and worship of the Protestant Episcopal Church in these United States.
This declaration remained in that form until the Constitution was completely revised by the General Convention of 1901. As so altered, the new declaration of canonical obedience required of all ordinands read:
. . . I do solemnly engage to conform to the Doctrine, Discipline, and Worship of the Protestant Episcopal Church in the United States of America.
The 1901 amendments also required the ordinand to "subscribe and make" the declaration of conformity; i.e., both to sign a written form of the declaration, and to repeat it orally at the service of ordination. However, the Book of Common Prayer was not revised to include the declaration in the service as such until 1979. And to do so, the revisers collapsed it in with the previously quoted ceremony of Exhortation, so that the two different forms of adjuration---one a response to a "calling out" to the ministry of Christ, and the other an affirmation of obedience to lawful canons---became hopelessly mixed and confused in purpose:
The Bishop says to the ordinand
Will you be loyal to the doctrine, discipline, and worship of Christ as this Church has received them? And will you, in accordance with the canons of this Church, obey your bishop and other ministers who may have authority over you and your work?
I am willing and ready to do so; and I solemnly declare that I do believe the Holy Scriptures of the Old and New Testaments to be the Word of God, and to contain all things necessary to salvation; and I do solemnly engage to conform to the doctrine, discipline, and worship of The Episcopal Church.The Ordinand then signs the above Declaration in the sight of all present.
Do you see what has happened here? For over four hundred years, the clergy of the Anglican Communion were called upon "to minister the Doctrine and Sacraments, and the Discipline of CHRIST" in such a way as to teach the people under their care "with all diligence to keep and observe" those things. Then the separate Declaration of Canonical Obedience was mingled in with that promise in a manner that confuses the "Discipline of CHRIST" with the "Discipline of this Church."
The recent charges and depositions against bishops and clergy for "abandonment of the Communion of this Church" have all grown out of this doctrinal confusion. What has happened is that the "Discipline of this Church" has eclipsed the "Discipline of CHRIST", to which "this Church" is and always must be subject. The Declaration of Canonical Obedience has been transformed into an Declaration of Disciplinary Obedience, from a commitment to obey "all such commands as the [Church] is by law authorised to impose" into an (imputed) requirement to obey "all such commands of the [Church] against which there is no law"---thereby turning the meaning of the original statement upside down.
General Convention, of course, enacts the Canons and makes changes to them. And, given the fact that Jesus Christ does not appear currently to have sufficient representation in General Convention, that is the Church's current problem in a nutshell.