Kitab-i-Aqdas/Elder146

It has been ordained for you that you make pure (lawful) your food and other things by paying the poor-rate. [note 1] This is what He who sent down the verses commanded in this Inaccessible Parchment. We shall tell you in detail of the property on which the poor-rate is paid when God wills and desires. He willed to detail what He wishes by a knowledge which He has. He is the Wise and the Knower.