Take only that much of goods from the world as are absolutely necessary for your earthly sojourn. If you want to be saved from the mischief of the world, then consider your wealth and dust as equal.

The zakāh in merchandise, like that in gold and silver, [is one-fourth of 10 percent for the year].

If a person decides to invest a part of his income, the year will not be reckoned until he actually purchases something with it, for the mere intent to invest is not enough.

The zakāh due on the profits which accrue to the money-lender is due on the lender himself, i.e. on his share of the profit, even before the division of the shares takes place. This is the most regular practice.

Know that the payer of the zakāh should observe five things: Intention, which means that the person should purpose in his heart the payment of the ordained zakāh, but he does not have to specify the property for which he pays the zakāt. […] Promptness in paying zakāh at the end of each year and on breaking the fast of Ramadān. […] That no substitute based on the value of the zakāt be offered in its stead. […] That the sadaqah should not be transferred from one town to another. […] Consequently, let the zakāh be spent in the town wherein it was collected. […] That the payer of the zakāh should divide the sum which he pays among the different groups of beneficiaries found in his home-town.

Know that he who seeks the road of the hereafter through the zakāh has certain duties to fulfill. These are as follows: The first duty is to understand the reasons why the zakāh is obligatory, to comprehend its significance, to find out how it constitutes a criterion wherewith man's devotion to God is tested and tried, and finally why it has been made one of the [five] pillars of Islam although it is merely a financial transaction and does not form a part of bodily worship.