Unfortunately, the Episcopalian must do a bit of additional research to arrive at the conclusions that I have. The article which I am referencing was deleted (somewhat) from the 1801 Protestant Episcopal version of the Articles of Religion, for political reasons, however, the text of the original article is preserved in the American Prayer Books regardless. The text that I have in mind is the 21st Article, which reads:
GENERAL Councils may not be gathered together without the commandment and will of princes. And when they be gathered together, forasmuch as they be an assembly of men, whereof all be not governed with the Spirit and word of God, they may err and sometime have erred, even in things pertaining to God. Wherefore things ordained by them as necessary to salvation have neither strength nor authority, unless it may be declared that they be taken out of Holy Scripture.This article is generally problematic in the American context because it assumes that councils of the Church will be convened under the authority of the Princes. Obviously, America does not have princes. General Convention is usually thought of as a "general" council of the Church, in this land, since the Protestant Episcopal Church is the part of the Catholic Church residing in these United States. The authority of General Convention can be thought of as under the authority of the bishops, without going off tangent on the nature of how a council is convened. The part of this article that interests me is the latter half. However, before discussing that part, let us recall briefly what authority the Church has. "The Church hath power to decree rites or ceremonies and authority in controversies of faith" which teaches in contrary to some other Protestant traditions, because the visible Church does have authority over several things. However, the Church may not "ordain anything contrary to God's word written, neither may it so expound one place of Scripture, that it be repugnant to another." The Church does not have authority to do these things according to our Articles of Religion. (Later on, we will discuss what to do when the Church does do these things). The last part of Article 20 offers additional perspectives on the authority of the Church, "Wherefore, although the Church be a witness and a keeper of Holy Writ: yet, as it ought not to decree anything against the same, so besides the same ought it not to enforce anything to be believed for necessity of salvation," meaning that the Church should not enforce anything which is not contained in Holy Scripture, or which is condemned therein.
Returning to the content in Article 21, we see again that General Councils "hath erred" and will continue erring, because, "forasmuch as they be an assembly of men, whereof all be not governed with the Spirit and word of God" meaning that not all General Councils are guided by God's Spirit and do not teach the truth, rather, "they may err and sometime have erred, even in things pertaining to God." This statement says two things, first, they may and have erred in things human, such as is our condition, but they have also erred in their teaching about God, such as General Convention has done (multiple times, might I add).
The final question is, what should we do if General Convention (or any council) declares to be truth that which is not taught in Scripture? Article 21 gives us the answer, "Wherefore things ordained by them as necessary to salvation have neither strength nor authority, unless it may be declared that they be taken out of Holy Scripture." Because these declarations have no Scriptural warrant, they have no authority, and are nothing more than declarations of men. We have no obligation to follow them, rather, we should continue to teach the truth of Scripture (and of the Episcopal Church, might I add, see what our Prayer Book and Canons teach about marriage). Because they lack any authority of God and his Word Written, these declarations also lack any "strength", they should not take over us as Christians, as God's chosen people. We have the Truth on our side, with that we have nothing to fear, nor should we give the attention due to these false teachers, other than ignoring their "work" and teaching Christ's Truth instead.