Is fulfilling an oath sworn by another person obligatory?
General Chapter
Al-Mughni
Book of Oaths
Primary text
The Prophet (peace be upon him) commanded the fulfillment of an oath sworn by another, as narrated by Al-Bukhari. This command is understood to be recommended (nadb), not obligatory (wujub). This is evidenced by Abu Bakr swearing an oath to the Prophet (peace be upon him) to be told what he erred in, to which the Prophet responded, 'Do not swear, O Abu Bakr,' and he did not inform him. If fulfillment were obligatory, he would have informed him.
Supporting text
An alternative view suggests that fulfilling the oath is obligatory if it does not involve harm. The Prophet's refusal to fulfill Abu Bakr's request could be due to the perceived harm involved. Furthermore, agreeing to the form of what was sworn to, while avoiding the intended meaning when the meaning is impossible to fulfill, is praiseworthy. This is shown when the Prophet (peace be upon him) placed his hand in the hand of a man brought by Al-Abbas to pledge allegiance for Hijra (migration), stating, 'There is no Hijra after the Conquest.' When Al-Abbas swore the Prophet to pledge allegiance, the Prophet took his hand and said, 'I have fulfilled my uncle's oath, and there is no Hijra,' thereby agreeing to the form of the pledge without affirming the intent behind the oath regarding the cessation of Hijra.