During the time of the Prophet, may Allah bless him and grant him peace, and of Abū Bakr, ‘Umar, ‘Uthmān and ‘Alī, there was no openly practised “marriage arranged to make a woman lawful again for her former husband” known to the witnesses, the woman and her guardians. Nor has anyone reported that the Prophet, may Allah bless him and grant him peace, or his Rightly Guided Caliphs restored a woman to her former husband through such a marriage. For divorces at that time generally followed the Sunnah, and people did not swear oaths invoking divorce. Thus, no specific report has been transmitted from the Companions concerning such oaths; what has been transmitted from them concerns actually pronouncing divorce, not swearing by it.

The distinction between divorce and swearing by divorce is clear, just as there is a recognized distinction between making a vow and using a vow as an oath. If a man seeks something from Allah and says, “If Allah cures my illness, settles my debt or delivers me from this hardship, I pledge to Allah that I will give a thousand dirhams in charity, fast for a month or free a slave,” this is a conditional vow which he must fulfil, according to the Quran, the Sunnah and scholarly consensus.

But if he makes a vow conditional in the manner of an oath, saying, “If I travel with you”; “If I arrange so-and-so’s marriage”; “That I should strike so-and-so”; or “If I do not leave you”—followed by “then I must perform Hajj,” “then my wealth is to be given in charity,” or “then I must free a slave”—then, according to the Companions and the majority of scholars, he is swearing an oath by a vow, not making a vow. If he does not fulfil the obligation he has undertaken, expiation for an oath suffices him.

Likewise, the Companions ruled that if someone said, “If I do such-and-such, every slave I own is free,” this constituted an oath, for which expiation for an oath sufficed. Many of the Successors likewise held this view concerning all these matters when al-Hajjāj ibn Yūsuf introduced the practice of making people swear oaths of allegiance—oaths invoking divorce and the freeing of slaves, oaths sworn in Allah’s name, and pledges to give one’s wealth in charity. It was also said that these included pledges to perform Hajj—