Must a person who previously acknowledged a gift, completion of a pledge, or receipt of sale price, and then retracts, administer an oath to his opponent?
General Chapter
Al-Mughni
Book of Acknowledgment of Rights
Primary text
If a man acknowledges that he gave a gift and delivered it, or pledged and delivered it, or acknowledges receiving the price of a sold item, or that a tenant took possession, and then denies it and asks his opponent to swear an oath, there are two narrations. One is that he is not made to swear, which is the position of Abu Hanifa and Muhammad, because his current claim contradicts his prior admission, so it is not accepted, similar to when an investment manager admits a profit and then says, 'I erred.' Furthermore, acknowledgment is stronger than evidence, and if evidence testified to it, he could not demand an oath along with his evidence, so similarly here.
Supporting text
The second narration is that the opponent must swear the oath. This is the position of Al-Shafi'i and Abu Yusuf because it is customary to acknowledge receipt before actual physical delivery, so what the retracting party says is potentially true, requiring the opponent to swear to negate this possibility. This situation differs from evidence because acknowledgment of receipt often precedes actual possession, whereas testimony about prior possession is not customary, as it would constitute false testimony. Second, denying an acknowledgment is contrary to and invalidates the acknowledgment, unlike testimony.