I disagree, Martin. Perhaps there is more than one way of thinking about what it means for something to be a foundation of something else? Foundations and their buildings, while distinct, form one composite thing, do they not? One way in which the Apostles might continue to function as a foundation of the Church might be through the continuation of the ministry. Clement (and our mutual friend Augustine) seems to have thought this. So, as I suggested before, I don’t think the matter can be clinched and victory declared by the use of the word “foundation” in Ephesians 2:20.
I think your understanding of “qualifications” here needs to be interrogated a little bit. As I understand it, your view appears to rest mainly on Acts 1:21-22. That is, that Matthias was qualified because he had travelled with and seen the Risen Lord. Thus, as that generation of eyewitnesses has passed, the ministry must also have passed. Is that right? My objection would be that it’s not clear that this passage is laying down qualifications in the absolute sense. Wouldn’t it disqualify Paul who was not one who “…companied with us all the time…” ? So, while I think this passage tells us how and why the nascent Church chose Matthias, I don’t think that the passage can be used against the continuation of the ministry in the post-Apostolic age.
I also don’t think that the other verses:
2 Peter 1:16,
1 John 1:1-3, 1 Corinthians 9:1, 1 Corinthians 15:8
Galatians 1:11-12 can be easily recruited into your argument either. I agree that John, Peter and Paul saw the Risen Lord! I agree that Paul was an Apostle! No argument here! But I don’t think that these verses really address the matter under discussion, which is whether the ministry can continue on without the original gang. I think that using any one of them as indirect proofs for the cessation of the Apostolic ministry only works if we
assume in advance that the Apostolic ministry cannot continue without the successor being a first-century Christian. So it looks to me like you are begging the question here.
To clarify my view, which you might have already guessed, I do not think that it is necessary for one to be a captial A Apostle and yet genuinely continue the ministry.