Is one entitled to claim money promised by a friend, despite swearing by Allah and uttering the phrase "I don't want it" in a moment of extreme anger, and later claiming to have forgiven?

A friend is obligated to fulfill a promise of money if it was an agreement for an exchange, with the burden of proof on the claimant and the oath on the defendant. However, if it was a pure promise of a gift, the majority of jurists hold that he is not obligated to fulfill it, because a gift is not binding until it is taken possession of, and the giver can retract it before that. If a person waives their right, they are not permitted to claim it afterward, even if they were in a state of anger, because there is no retraction from an acquittal, unless the waiver was due to an error in judgment on the part of the one who was to swear.