as recorded by al-Bukhari from Ibn ʿAbbas, the Prophet—may Allah bless him and grant him peace—said:

“If people were granted their claims merely by asserting them, men would lay claim to the lives and property of others; rather, the oath is incumbent upon the defendant.”

Thus, when the claimant possesses nothing but a bare allegation, the defendant’s position outweighs his, because two presumptions stand in the defendant’s favor: possession is presumed rightful, and liability is presumed nonexistent. Yet it is possible—indeed frequent—that the claimant is truthful while lacking evidence. His claim is therefore not dismissed solely on the basis of those presumptions; instead, the defendant is ordered to swear an oath. That oath, combined with the presumptions, constitutes proof. Hence the defendant’s denial counters the claimant’s assertion: both are statements whose truth is unknown, they conflict, and the defendant gains the upper hand by virtue of the underlying presumption. The status quo therefore remains; the claimant is not awarded what he seeks on a mere assertion, nor is his right to pursue the matter extinguished, for the defendant has produced no proof that would rebut the claim. Once the defendant swears, however, his oath becomes decisive proof, ending the dispute and terminating the claim.

If the defendant refuses to take the oath and the claimant still brings no evidence, the majority of scholars suspend judgment. Some rule against the defendant because of his refusal, treating that refusal either as a substitute for the demanded duty or as an implicit confession. The larger body of scholars, however, holds that the oath should then be redirected to the claimant—the one who asserts that he has knowledge