The Kitáb-i-Aqdas
Notes
125.Should anyone acquire one hundred mithqáls of gold, nineteen mithqáls thereof are God’s and to be rendered unto Him   ¶97
This verse establishes Ḥuqúqu’lláh, the Right of God, the offering of a fixed portion of the value of the believer's possessions. This offering was made to Bahá’u’lláh as the Manifestation of God and then, following His Ascension, to ‘Abdu’l-Bahá as the Centre of the Covenant. In His Will and Testament, ‘Abdu’l-Bahá provided that the Ḥuqúqu’lláh was to be offered “through the Guardian of the Cause of God.”1 There now being no Guardian, it is offered through the Universal House of Justice as the Head of the Faith. This fund is used for the promotion of the Faith of God and its interests as well as for various philanthropic purposes. The offering of the Ḥuqúqu’lláh is a spiritual obligation, the fulfilment of which has been left to the conscience of each Bahá’í. While the community is reminded of the requirements of the law of Ḥuqúq, no believer may be approached individually to pay it.
A number of items in Questions and Answers further elaborate this law. The payment of Ḥuqúqu’lláh is based on the calculation of the value of the individual’s possessions. If a person has possessions equal in value to at least nineteen mithqáls of gold (Q&A 8), it is a spiritual obligation to pay nineteen percent of the total amount, once only, as Ḥuqúqu’lláh (Q&A 89). Thereafter, whenever one’s income, after all expenses have been paid, increases the value of one’s possessions by the amount of at least nineteen mithqáls of gold, one is to pay nineteen percent of this increase, and so on for each further increase (Q&A 8, 90).
Certain categories of possessions, such as one’s residence, are exempt from the payment of Ḥuqúqu’lláh (Q&A 8, 42, 95), and specific provisions are outlined to cover cases of financial loss (Q&A 44, 45), the failure of investments to yield a profit (Q&A 102) and for the payment of Ḥuqúq in the event of the person’s death (Q&A 9, 69, 80). (In this latter case, see note 47.)
Extensive extracts from Tablets, Questions and Answers, and other Writings concerning the spiritual significance of Ḥuqúqu’lláh and the details of its application have been published in a compilation entitled Ḥuqúqu’lláh.
 
1 Will and Testament of ‘Abdu’l-Bahá, p. 15