"The oath adds nothing to the obligation. For a covenant, if lawful, binds in the sight of God, without the oath, as much as with it; if unlawful, bindeth not at all, though it be confirmed with an oath."

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A covenant not to defend myself from force by force is always void. For ... no man can transfer or lay down his Right to save himself. For the right men have by Nature to protect themselves, when none else can protect them, can by no Covenant be relinquished. ... [The right] to defend ourselves [is the] summe of the Right of Nature.

— Thomas Hobbes