Basically, and help me if this sounds familiar, the Bishop of Bangor said that there is no biblical support for church government/authority of the church. William Law did not take kindly to this rank heresy and proceeded to literarily flay the bishop alive.
Again; I presume it may very justly be said, that the Christian Revelation hath some Effect towards the Salvation of Mankind; but then it hath not this Effect always and in all Cases, it is only effectual upon certain Conditions. Now if Excommunication can have no Effect, because it is not effectual when it is wrongfully pronounced, then the Christian Revelation can have no Effect towards saving those who embrace it as they should, because it has no such Effect on those who embrace it otherwise. The Reason of the Thing is the same in both Cases, and anyone may as justly set forth the Vanity and Insignificancy of the Christian Revelation, because it does not save all its Professors, as your Lordship exposes the Weakness and Vanity of spiritual Censures, because they do not absolutely, and in all Cases, throw People out of God’s Favour.