Marlo, you give four interesting examples.
The Assumption doesn’t work, IMHO, because the evidence for it is too late. It’s hard to believe that it was passed down orally for four or five centuries. I’m not going to say that those who think it was are clearly wrong, but it’s going to be hard to persuade Protestants of this.
I’m not quite sure I understand your point about the Lord’s Prayer. Certainly there are Protestants who claim that it’s a model rather than a form to be used, but that’s a matter of interpretation, not of oral tradition.
The Eucharist is a good example, but a difficult one because there is clearly development going on, and it’s hard to isolate just what allegedly was handed down orally. But it’s reasonable to suppose that a clearer understanding of the Real Presence (and perhaps some basic liturgical matters) was handed down orally. In particular, it’s possible that the idea of the Eucharist as sacrifice was an oral teaching.
Apostolic succession is the best example you’ve come up with, I think. Again, you can find a kernel of the idea in the Pastoral Epistles (and maybe even in the Gospels, though that’s less clear). And on the other hand, there’s obviously development there too. But given how certain Ignatius and Clement seem to be that the leaders of the Church received apostolic authority, it’s quite reasonable to think that the Apostles handed down something on this that is clearer than what we find in Scripture.
JaneFrances,
The intercession of the saints is an interesting example, but it seems to me that the practice clearly grew out of the veneration of martyrs, which militates against it being an apostolic tradition. I think the first example of a glorified saint being asked for prayers is from the 3rd century (the Marian prayer “Sub Tuum Praesidium”–I’m taking the word of Catholic apologist friends that this is from the 3rd century). So you could be right, but I think the evidence is shaky. It seems more plausible that this was a gradual development arising from martyr veneration on the one hand and the growing emphasis on the Virgin Mary on the other.
Edwin