The Kitáb-i-Aqdas - The Most Holy Book
Index term: and Huqúqu'lláh, under Wealth
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Question: When one's wealth exceeds nineteen, is it necessary for it to increase by a further nineteen before Huqúq is due again, or would it be due on any increase?
Answer: Any amount added to nineteen is exempt from Huqúq until it reacheth a further nineteen.