Abdullah bin Umar reported,

Two men brought a dispute before the Prophet ﷺ. The Messenger of Allah ﷺ asked the claimant for evidence, but he had none, so he called upon the defendant to swear an oath. The man swore by Allah, besides whom there is no god.The Messenger of Allah ﷺ then said, "You did indeed do it, but you have been forgiven because of the sincerity with which you said, 'There is no god but Allah.'"

حدثنا حسن حدثنا حماد بن سلمة عن ثابت البناني عن ابن عمر عن النبي ﷺ بمثله إلا أنه قال أخبرني جبريل ﷺ أنك قد فعلت ولكن الله غفر لك