The Pen of the Most High hath ordained that the Huqúqu’lláh is payable on nineteen mithqáls of gold. That is, the Ḥuqúq is levied on money equalling this amount. As to other possessions in silver or otherwise, it is payable when they equal this in value, not in number. The Huqúqu’lláh is payable only once; for example, if a person acquireth a thousand mithqáls in gold and payeth the Huqúq thereof, the Right of God ceaseth to be applicable to that amount, except in regard to what accrueth to it through commerce and transactions; when such profits reach the prescribed minimum, one must carry out what God hath decreed. When, however, the original sum changeth hands, the Huqúq is again payable as it was the first time; in this event the Right of God must be given.
Beseech ye God—magnified be His glory—to grant that His loved ones may be privileged to take a portion from the ocean of His good-pleasure, for this would serve as the means for the salvation of mankind, and may of their own accord carry out that which would purify them and cause them to attain everlasting life....
- Baha’u’llah (‘Additional Tablets and Extracts from Tablets Revealed by Bahá’u’lláh’; Baha’i Reference Library of the Baha’i World Center)