Final answer:
Kate supports the theory of the Divine Right of Kings, implying that her husband has a god-given right to rule over her, making her loyalty and support unquestionable.
Step-by-step explanation:
Kate's stance that her husband should be her 'lord, keeper, life, etc.' supports the theory of the Divine Right of Kings. This old theory posits that a monarch is subject to no earthly authority, deriving the right to rule directly from the will of God. The doctrine implies that any attempt to overthrow the monarch, resist their commands, or question their decisions is tantamount to questioning the will of God.
Through this view, the monarch becomes not just the political ruler but also a spiritual overseer, justifying the expectation that subjects, including the monarch's spouse, should be unquestioningly loyal and supportive. In the context of a marriage dynamic, this could translate into a belief in a traditional hierarchical structure within the family unit, with the husband being the unequivocal head.