I read Dr. McGraws article, which was very well done and helpful. I agree with the large share of it.
At times he says that the Benediction is 'more than a prayer'. I agree with this. A few times he says that the Benediction is not a prayer. I disagree with this (and I believe Westminster does too, as I have documented). He thus is ambiguous on whether the Benediction is a prayer or not, as is Rev. Silversides.
Also regarding the intent of the list of elements of worship in WCF 21.5
- It would seem that there not being a congregational 'Amen' in Westminster's Directory of Public Worship was due to the presbyterians, Independents and others not being able to agree to such. Corporately saying Amen was the practice of the Scots and the practice, by and large, of the English presbyterians. I am not sure about the Independents. But in any case, it seems to me it is part of the element of prayer, nonetheless.
- Regarding the votum and salutation (and possibly other parts of some church's worship services), while they have been a part of Dutch worship, they are not in Westminster's Directory of Worship. It seems less likely to me that this was simply because they couldn't agree to it, but rather that they did not think such things were derived from Scripture as distinct elements of worship. The Scots, at least, did not find these things in Scripture for the worship service and did not practice these things. The Independents certainly did not. I would have to check on the English presbyterians following Cartwright.
My point is that the English context of Westminster largely did not think such things were distinct elements of worship, and did not practice such, nor did they put them into their Directory. Hence they cannot be used as an argument that the list of worship elements in WCF 21.5 was intended to be open.
- When the Scots adopted the Westminster Directory of Public Worship, they put away things in their worship that were not in the Westminster Directory. Hence they interpreted the list in 21.5 as exhaustive and not allowing for other elements of worship (they continued, though, to use a corporate Amen, which as I mentioned, fits nicely under the element of prayer.)
For these reasons (and others), I think the case is strong that 21.5 is an exhaustive list of worship elements. If other elements of worship are in Scripture, and could be derived from Scripture, why would the divines not list them as such? To make a list of worship elements and yet not derive all that could be derived for such from Scripture, would be irresponsible.
Just my thoughts. Hope it is useful fodder.