Shaykh al-Islām also said:

A Comprehensive and Beneficial Section

The terms to which Allah has attached rulings in the Quran and Sunnah include the following:

Some have definitions and meanings known through revealed Law, as Allah and His Messenger have explained them. Examples include prayer, zakat, fasting, Hajj, faith, Islam, disbelief, and hypocrisy.

Others are defined by the language itself, such as the sun and moon, heaven and earth, and land and sea.

Still others are defined by people’s customary practices and usage, and thus vary with their customs. Examples include sale, marriage, taking possession, the dirham, the dinar, and similar terms for which the Lawgiver has prescribed no definition, nor is there a single definition shared by all speakers of the language. Rather, their measure and characteristics differ according to people’s customs.

Allah and His Messenger have explained whatever belongs to the first category. As for the second and third categories, the Companions and Successors addressed by the Quran and Sunnah understood what was intended, because they knew what these terms denoted, whether delimited by the language or left to people’s customary usage