The burial ground is now not simply a place where bodies are buried; it is also a place signifying the ultimate destiny of those buried there, and by metonymy, all who die and are buried at all times.

I agree that Jesus weaves other thoughts into the judgment motif, but the fact that he elaborates the thought does not necessarily mean that he extends its frame of reference. The other images, as you seem to allow, are also mostly drawn from Old Testament prophecies of judgment on rebellious Israel. Nothing that you have added takes us beyond the circumstances of first century Israel. Matthew 10:28 has no necessary universal implication: it simply means that the destruction of gehenna is final and total.

So we are still left with the question: What is the basis for extending what Jesus has to say about gehenna to the whole of humanity? You can’t just wave the magic wand of ‘metonymy’ over the verse and transform it into a universal principle!

It is not the martyrs who are ‘hellenized’ but the theology and outlook represented in the Maccabean writings. I have my doubts about the idea that the ‘soul’ is preserved after death in an ‘intermediate state’, but perhaps we can save that for another occasion.

It is therefore possible to use the vocabulary and imagery of Israel’s previous history to describe what is happening now, but it is not possible to confine their meaning exclusively to that of a previous phase in her history.

This is still only an unsubstantiated hermeneutical assertion. Why is it not possible? Where is the evidence that Jesus meant his words to be taken as directly relevant beyond the narrative about judgment and restoration? Where has this ‘principle of interpretation’ come from? It is, of course, possible that he saw potential in the imagery of gehenna for a universal application, beyond AD 70, but the texts do not compel this assumption. My argument would be that there are much better ways of connecting ourselves with the transforming power of the Gospel story, which do not require us to read anachronistic notions into Jesus’ teaching.