Article 4 of the Trusts of Model Deed provides
"and upon further trust, to permit, in conformity with the doctrines, discipline, by-laws, rules and regulations of The United Church of Canada and not otherwise...";
the words "doctrines", "discipline", "by-laws", "rules" and "regulations" being equal for the purposes of the trust though the sources referenced by these words are not equal, so to not be "in conformity with...and not otherwise" with one of the words is equally a breach of trust as with any of the other words.

The context of doctrine and polity is illustrated by Gershom W. Mason, lawyer representing the church through the union years and after, in The Legislative Struggle for Church Union, [The Ryerson Press, Toronto, 1956 pp. 93-101, 108-125], quoting resolution carried by a majority of 426 to 96, General Assembly of the Presbyterian Church in Canada, June 9, 1924
"1. In view of the fact that the right of the Church to restate its own faith, to shape its own polity and to determine its own destiny has been challenged and that the whole question of the spiritual independence of the Church has definitely arisen, this General Assembly of the Presbyterian Church in Canada sets forth the following as expressing its conviction regarding the liberty of Christ's Church in matters spiritual. This Church has the right and power, subject to no civil authority, to legislate and to adjudicate finally in all matters of doctrine, worship, government and discipline in the Church, to frame, adopt and modify its subordinate standards of faith, and the right to unite with any other Christian Church without loss of its identity on terms which it finds to be consistent with its own principles, doctrine and religious standards.
"2. This Assembly must, therefore, decline to accept the amendments which have been introduced into the Preamble of the Church Union Bill now before Parliament as invading and violating these rights. This Assembly respectfully urges the Parliament of Canada to pass during this session the Church Union Bill without any amendment which would invalidate the principle of the Bill." [p. 100]
For Mason context is that the church has the right to legislate and to adjudicate finally in all matters of doctrine, worship, government and discipline as opposed to being "bound forever to the standards of the 17th century" [pp. 112-113], not that context gave the church the right to arbitrarily change its public expression without process.

To interpret 'not' what the doctrinal articles presently say 'is' is not interpretation, it is completely different thought [the assertion that the doctrinal articles are a summary does not disqualify the thought within the articles] and is a breach of the trusts attached to property.

The Congregational Board of Trustees Handbook provides
"34. What happens if a use of the property inconsistent with the uses contemplated by the Trusts of Model Deed is proposed?
"The Board of Trustees is obligated not to allow the property to be used for a purpose inconsistent with the uses contemplated by the Trusts of Model Deed. If such is about to happen, the recourse of the Board of Trustees is not to cooperate in any such dealing, and further to notify the Official Board or Church Board or Church Council, and if that proves ineffectual, then to notify the Presbytery requesting an investigation and decision, and if that proves ineffectual, then to resign." [p. 31]

The Basis of Union is the authority under which the United Church of Canada functions.

The United Church of Canada Act provided
"The Basis of Union set forth in Schedule A to this Act is hereby ratified and confirmed as such, and in so far as the terms and provisions thereof relating to polity and administration are not inconsistent with the provisions of this Act they shall have the same force and effect as if expressly set out herein." [article 26];
"All Acts and portions of Acts of the Parliament of Canada inconsistent with the provisions of this Act are hereby repealed in so far as may be necessary to give full effect to this Act." [article 27];
"All resolutions passed by the General Council shall have the force and effect of by-laws..." [article 24];
"Subject to the provisions of section eight hereof, all property, real and personal, belonging to or held by or in trust for or to the use of any congregation of any of the negotiating churches, shall, from and after the coming into force of this Act be held, used and administered for the benefit of the same congregation as a part of The United Church in the manner and upon the trusts and subject to the terms and provisions set forth in Schedule B to this Act, and all property, real and personal, thereafter acquired for or belonging to or held by or in trust for or to use of any congregation of The United Church shall be held, used and administered for the benefit of the said congregation as a part of The United Church upon the said trusts and subject to the said terms and provisions..." [article 6];
note: The United Church of Canada Act takes precedence; the effect of previous legislation was only repealed to the extent necessary; making statement the church could not legislate without remit is questioned; and the Trusts of Model Deed is a separate Schedule B [the church can change that which the trusts reference, doctrines, discipline, by-laws, rules and regulations, but not the trusts].

The Methodist Union of 1884 described the trusts attached to property in the Trusts of Model Deed which included doctrinal provisions [article 3], and applied those doctrinal provisions to the governance of the denomination [article 14]
"And it is hereby declared that the "Rules and Discipline and General Usage" of the said Methodist Church in these presents mentioned or referred to, are the Rules and Discipline of the said Church, as printed and published by authority of the said conference, in a book entitled "Doctrines and Discipline of the Methodist Church," and the general usage and practice of the societies belonging to said church, and such rules and regulations as may, from time to time, be made or adopted by the said general conference, and printed and published in their journals, in accordance with the provisions contained in the said book of discipline, but subject at all times to the proviso respecting doctrines in these presents contained."

The Presbyterian Church in Canada did not have the equivalent of a Trusts of Model Deed, but the Book of Forms set forth
"For the sole use and benefit of the said congregation, for the site of a church or meeting house, burial ground, and residence for the minister (as the said congregation may from time to time direct), and for the support and maintenance of public worship, and the propagation of Christian knowledge, according to the doctrines, discipline and modes of worship of the said The Presbyterian Church in Canada."
to be included with the title to property, and applied those doctrinal provisions to the governance of the denomination.

Article 15 of The United Church of Canada Act required
"Where, prior to the coming into force of this section any existing trust has been created or declared in any manner whatsoever for any special purpose or object having regard to the teaching, preaching or maintenance of any principles, doctrines or religious standards, or to the support, assistance or maintenance of any congregation or minister or charity, or to the furtherance of any religious, charitable, educational, congregational or social purpose, in connection with any of the negotiating churches, such trust shall continue to exist and to be performed as nearly as may be for the like purposes or objects in connection with The United Church..."
though
"as The United Church may determine..."
provides that the church could determine otherwise,
"...and anything done in pursuance of this Act shall not be deemed to be a breach of any such trust but shall be deemed to be in compliance therewith and a performance thereof, and the entry of any congregation into The United Church shall not be deemed a change of its adherence or principles or doctrines or religious standards within the meaning of any such trust."
with article 14, permits the church to change its "doctrine, worship, discipline and government" per article 28(b)
"That nothing in this Act contained shall be deemed to limit the independent and exclusive right and power of The United Church to legislate in all matters concerning its doctrine, worship, discipline and government, including therein the right and power from time to time to frame, adopt, alter, change, add to or modify its laws, subordinate standards and formulas and to determine and declare the same or any of them, but subject to the conditions and safeguards in that behalf contained in the Basis of Union."
further expressed in basis article 24
"The General Council shall have full power:
"(2) (a) To legislate on matters respecting the doctrine, worship, membership and government of the Church, subject to the conditions: First, that before any rule or law relative to these matters can become a permanent law, it must receive the approval of a majority of the Presbyteries, and, if advisable, pastoral charges also; Second, that no terms of admission to full membership shall be described other than those laid down in the New Testament; and, Third, that the freedom of worship at present enjoyed in the negotiating Churches shall not be interfered with in the United Church.
"(b) To legislate on all matters respecting property, subject to the limitations elsewhere provided in this Basis of Union, and subject also to the approval of the Conference in which the property is situated."
without such change being "deemed to be a breach of any such trust..."; to arbitrarily change that which the trusts reference is a breach of the trusts attached to property.
__________

Bibliography

Allan Farris, 'The Fathers of 1925', The Tide of Time, edited by John S. Moir, Knox College, 1978
C. E. Silcox, 'Church Union in Canada', Institute of Social and Religious Research, New York, 1933
Donald John MacRae Corbett, 'The Canadian Church Union of 1925 and the Law', Caven Library, Knox College 1957
E. Lloyd Morrow, 'Church Union in Canada' [Its History, Motives, Doctrine and Government], Thomas Allen Publisher, Toronto 1923
Gershom W. Mason, 'The Legislative Struggle for Church Union', The Ryerson Press, Toronto 1956
John H. Young, 'Sacred Cow or White Elephant? The Doctrine Section of the Basis of Union', Touchstone Volume 16 May, 1998 Number 2
John S. Moir, 'Enduring Witness' [A History of the Presbyterian Church in Canada], Presbyterian Publications, Toronto 1974
John Webster Grant, 'The Canadian Experience of Church Union', Lutterworth Press, London 1967
N. Keith Clifford, 'The Resistance to Church Union' UBC Press, Vancouver 1985 ISBN 0-7748- 0212-X
Randolph Carleton Chalmers, 'See the Christ Stand' [A Study in Doctrine in The United Church of Canada], Ryerson, Toronto 1945
The Presbyterian Church in Canada, 'Rules and Forms of Procedure in the Church Courts of the Presbyterian Church in Canada', The Westminster Co., Limited, Toronto 1909
The United Church of Canada, 'Congregational Board of Trustees Handbook', Etobicoke 2002
The United Church of Canada, 'Public Statements and the United Church of Canada', 1991
The United Church of Canada, 'The Manual', United Church Publishing House, 2001
Thomas Buchanan Kilpatrick, 'Our Common Faith', The Ryerson Press, Toronto 1928 ['With a Brief History of the Church Union Movement in Canada', Kenneth H. Cousand]

Acts of Parliament
Canada Province
1861 c. 124 An Act respecting the Union of certain Presbyterian Churches therein named
Canada
1884 c 106 An Act respecting the Union of Certain Methodist Churches therein named
1910 c. 86 An Act to incorporate the Congregational Union of Canada
1912 c. 116 An Act respecting the Methodist Church
1924 c. 100 The United Church of Canada Act
Manitoba
1990 c. 200 The United Church of Canada Act
Ontario
1872 c. 107 An Act to enable the Trustees of the several Congregations...
1873 c. 144 An Act respecting the Methodist New Connection Church of Canada
1874 c. 75 An Act respecting the union of certain Presbyterian Churches therein named
1874 c. 78 An Act respecting the Methodist Church of Canada
1887 c. 237 An Act respecting the Property of Religious Institutions
1900 c. 135 An Act incorporating the Board of Trustees of the Presbyterian Church in Canada
Saskatchewan
1924 c. 64 The United Church of Canada Act
Other
1921 c. 29 Church of Scotland Act

Faith Statements
Westminster Confession of Faith 1647 [Presbyterian Church in Canada]
Articles of Religion [Methodist Church]
The Commission Creed of 1883 [Congregational Churches of Canada]
Doctrinal Articles [The United Church of Canada]