Looks like it was removed in 1827. I don't actually remember having to say anything at any of my graduation ceremonies there (BA, MA, DPhil), just walking on to the stage. I do wonder if at matriculation we all had to make some oath together but I think I would have remembered if that had been the case. I have a strong feeling though I might have had to make an oath when I became a scholar - there was definitely a ceremony we had to go to - but that would have been college-dependent.

You'll have collectively said "do fidem". The rest is read by the official at the table, not the graduands.

The question as to whether this constitutes swearing an oath or making a simple promise was an interesting one for me as Quakers traditionally refuse to do the former.