The 'aam (lit. 'general') is a word that applies to all the members of a specific set, no matter how small or large that set is. For example, Allaah says:
"Every soul shall taste death." (Q3 [Aal-Imraan]: 185)
This verse is applicable to every soul, be it human, animal or jinn.
Khaas (lit. 'specific'), on the other hand, is a word that is used to denote a limited number of things, including everything to which it can be applied. The primary difference between 'aam and Khaas is that Khaas applies to a single subject or a specified number of objects; in other words, the scope of its application is limited, unlike the 'aam.
There are three categories of 'aam:
I) 'Aam that is totally unspecified. This is rare in the Qur'an. An example of this is the verse:
"Allaah is aware of all things." (Q4[Nisaa]: 176)
since there are no exceptions to this verse.
2) 'Aam in wording, but Khaas in meaning. This is uncommon in the Qur'an. An example of this is the verse:
"Then depart from whence the people depart." (Q2 [Baqarah]: 199)
The 'people' referred to in this verse are the other tribes of Arabia besides the Quraysh. Even though the wording seems to be 'aam (i.e., all people), the meaning is in fact khaas (i.e. the tribes of Arabia).
3) 'Aam that has been specified. This is the most common type of 'aam in the Qur'an. An example of this is the verse:
"Forbidden to you (in marriage) are ... your step daughter ... who have been born of your wives with whom you have had intercourse ..." (Q4[Nisaa]:23)
This verse has specified an 'aam in that only a specific type of step-daughter is forbidden in marriage.
These two complimentary categories are primarily used together in deducing the laws of the Sharee'ah. The Qur'aan might give a general ruling in one place, yet another verse or hadeeth may specify that rule not to apply in certain circumstance.
This article was culled from the publications of Deen Communication Limited