[drummojg]

What I keep thinking of following this is from Matthew 5:

> Again, you have heard that it was said to the ancients, ‘Do not break your oath, but fulfill your vows to the Lord.’ 34But I tell you not to swear at all: either by heaven, for it is God’s throne; 35or by the earth, for it is His footstool; or by Jerusalem, for it is the city of the great King...

Implying that even in a religious context, one might swear on "one's mother's grave"in the metaphorical sense. So then I think there must be a natural and historical reverence to oaths in general, which sends my mind down more Neil Gaiman-ish paths. I would bet that the significance of an Oath is older than every extant religion.