Are oaths indissoluble

i) According to Biblical ethics, are oaths irrevocable? In the Mosaic law, a father can nullify the oath of a teenage daughter. In that particular respect, the oath is dissoluble. 

It's unclear whether that's because the party is a minor or a female minor. Is it just that she's underage? Or is it that she's still single and living under her father's roof, which puts her under his authority? 

ii) Then there's the famous case of Jephthah's vow. In narrative theology, the narrator will often recount an incident without editorial comment, so it's up to the reader to infer how to view the incident.

Intuitively, it's contradictory to say we ever have a moral duty to do something immoral. In that case, how can we acquire a moral duty to commit a wrong? 

So it seems as though Jephthah should have broken his vow rather than commit murder. It was morally wrong for him to make that vow in the first place. 

This goes to the conventional distinction between lawful and unlawful vows. Still, the account itself is silent on the moral status of his action. Admittedly, this occurs in a book designed to illustrate Israel's reversion to heathen depravity. 

iii) Then there's the difficult case of the Gibeonites, in Josh 9. They hoodwink the Israelites into making a peace treaty. Even after it turns out that the Israelite were snookered, they honor the treaty. 

That's counterintuitive because we normally think a contract entered into under false pretenses voids the contract. Yet God himself backs that treaty (2 Sam 21). 

So is our intuition mistaken, or do special circumstances make this case exceptional?

iv) Josh 9 involves a couple of dilemmas. The Gibeonites find themselves in a bind. They fear annihilation by the Israelites. So they seek a peace treaty. But how can they do so without divulging their identity as the enemy? And once they expose themselves, doesn't that leave them vulnerable to annihilation?

So they resort to subterfuge. It's possible that the treaty is honored in part due to the extenuating circumstances of the dilemma in which they found themselves. That may mitigate what would ordinarily be the culpability of their deception.

v) In addition, they act on faith. They fear Yahweh. So perhaps the treaty is honored, in part or in whole, because their action is a witness to the true God. They were submissive to Yahweh.

This may be similar to Jacob's trickery in Gen 27. Even though it was wrong to fool his father, his action ironically demonstrates a degree of faith, compared to his indifferent brother. Jacob puts his trust in Yahweh's promises. Although his behavior is manipulative, it's still a cut above Esau's casual impiety. 

vi) Finally, the Israelite leadership creates a dilemma for itself by failing to consult Yahweh before sealing the deal (9:14). Either way, they lose face. 

Given the extenuating factors in the account, on both sides, I don't think this case proves that oaths are absolute.