Third-person singular simple present indicative form of prove.(verb)
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Use "proveth" in a sentence
"The exception proveth the rule, not the exception."
"By the truth of the Messiah, thou hast proved thyself with me a man of keen wit; but now I see what mischief there is in thy heart, and how thou canst permit thyself a speech which proveth thy traitorous intent."
"To subordinate prophets of perpetual calling, I find not any place that proveth God spake to them supernaturally, but only in such manner as naturally He inclineth men to piety, to belief, to righteousness, and to other virtues all other Christian men."