Is a foundation once and for all?

1. Once more I'm going to comment on Eph 2:20. This is the primary cessationist prooftext. I agree with cessationists that the Apostolate was a temporary arrangement which died out with the last apostle. Likewise, I agree with cessationists that the epoch of prophecy in the sense of public revelation is behind us. 

2. In my experience, the cessationist appeal to Eph 2:20 is circular. They implicitly argue that the foundation is once and for all time because the apostolate is once and for all time while the apostolate is once and for all time because the foundation is once and for all time. So what's the logical connection? What grounds the conclusion? 

If you think the Apostolate is unrepeatable, then by definition an apostolic foundation is unrepeatable. Conversely, if you think a foundation is unrepeatable, then by definition an apostolic foundation is unrepeatable. It seems to me that cessationists oscillate between these two criteria without clarifying the logical relation or direction of the inference. You can't use each to prove the other. If you already know, apart from Eph 2:20, that the apostolate is unrepeatable, then you might use that to establish the unrepeatability of the foundation, or vice versa. If, however, you're using this verse to establish the unrepeatability of the apostolate in the first place (or the unrepeatability of the foundation in the first place), then the appeal is viciously circular. It takes for granted the very thing you need to prove. 

3. Another issue concerns what the foundation is. 

i) I'm not posing a grammatical or syntactical question in terms of how to render the Greek phrase, but a conceptual question regarding the larger idea that Paul intends to convey. 

ii) Should we understand the claim to be that the foundation just is the apostles and prophets? Are they foundational simply in virtue of being apostles and prophets, even if they said or did nothing? Does the foundation consist of the apostles and prophets in that regard? I don't see how that makes any sense. 

Or is the phrase a shorthand expression for the foundation which they laid? Their unique activities? If so, which apostolic and prophetic activities are foundational? 

Is the composition of the NT the foundation? But that's both broader and narrower. Broader inasmuch as the apostles and prophets did other things in besides that. Narrower inasmuch as not all or even most of them contributed to the composition of the NT.

iii) Another candidate might be church-planting, witnessing to Jews, witnessing to Roman dignitaries. If so, that principle doesn't have a 1C cutoff. They only planted churches in some localities of the Roman Empire. Only witnessed to some Jews and some Roman dignitaries.

iv) On that view, the foundation may be continually or periodically extended by planting additional churches, evangelizing new people-groups. Indeed, to play with the metaphor, sometimes congregations outgrow the original foundation, so it's necessary to expand the foundation. Build additions or annexes. 

Dropping the metaphor, when, after the death of the apostles, churches were planted in N. Europe, E. Europe, Asia, N. & S. America, China, Japan, &c. doesn't that extend the foundation?

v) Conversely, some countries that were originally evangelized lose the foundation. Where's the church of Ephesus c. 2018? In that missionary sense, it will be necessary to lay a new foundation. 

4. In sum, I think the cessationist appeal to Eph 2:20 fails. That doesn't mean cessationism is wrong. It's always tempting to settle a theological dispute by appeal to a single trump card. That's very convenient, if available. But many theological positions resist refutation at one stroke. They have multiple justifications. Nowadays, for instance, it's customary for sophisticated cessationists to mount an argument based on redemptive-historical theology. A whole paradigm rather than a single decisive prooftext.