The Book of Īlāʾ
It is a husband’s oath by Allah Most High, or by one of His attributes, to refrain from intercourse with his wife in her vagina for more than four months, …
His statement—may Allah Most High have mercy on him—“Īlāʾ”: īlāʾ means taking an oath, and aliyya means an oath. It is the verbal noun of ālā yuʾlī īlāʾan, a quadriliteral verb, as indicated by its pattern, which is like ikrām, from akrama yukrimu ikrāman. Linguistically, it means an oath. Allah Most High says:
“For those who swear abstinence from their wives, there is a waiting period of four months.” [al-Baqarah 2:226]
In the Sacred Law, however, it is restricted in meaning. Legal definitions are generally narrower than their linguistic meanings, while linguistic meanings are generally broader. Thus, ṭahāra linguistically means cleanliness and freedom from impurity, whereas in the Sacred Law it has a more specific meaning. Ṣalāh linguistically means supplication, whereas in the Sacred Law it has a more specific meaning: worshipping Allah through prescribed words and actions. Zakāh means growth and increase linguistically, whereas in the Sacred Law it has a more specific meaning. Thus, legal definitions are generally narrower than linguistic meanings, except in one matter: faith. Linguistically, faith means affirmation; in the Sacred Law, it is affirmation entailing acceptance and submission. It therefore includes speech and action. Thus, faith consists of belief in the heart, speech of the tongue, and actions of the limbs.
In the Sacred Law, the author—may Allah Most High have mercy on him—defines īlāʾ as follows:
“It is a husband’s oath by Allah Most High, or by one of His attributes, to refrain from intercourse with his wife in her vagina for more than four months.”
His statement, “a husband’s oath,” means that the oath of someone who is not a husband is neither īlāʾ nor valid as such. Thus, if he says, “By Allah, I shall not have intercourse with this woman for one year,” and then marries her, his oath is not īlāʾ, because at the time