The oath merely negates the obligation to pay in outward appearance, yet it does not negate the right that remains in his liability. For this reason, if evidence is established against him after his oath, he is obligated, and the guarantor is also obligated.

Section: If the guarantor claims that he has paid the debt, but the guaranteed party denies it and he has no evidence, the statement of the guaranteed party is accepted, because he is claiming the delivery of property to one whom he did not entrust with it (21); thus, the statement of the denier is accepted. He has the right to demand payment from whichever of the two he wishes. If he has recourse against the guaranteed party, can the guarantor have recourse for what he paid on his behalf? We must consider: if he does not acknowledge the payment, he has no recourse against him. If he does acknowledge the payment, but it was paid without evidence in the absence of the guaranteed party, he has no recourse for anything, whether the guaranteed party confirms or denies it, because he authorized him to make an exonerating payment, and that was not achieved. If he paid it with evidence, the right is established by it; however, if (22) it is dead or absent, the guarantor has the right to have recourse against the guaranteed party (23), because he acknowledges (24) that he neither fell short nor was negligent. If he paid it with evidence that is rejected due to an obvious matter, such as disbelief or open corruption (fisq), the guarantor has no recourse due to his negligence, because this evidence is like its absence. If it was rejected due to a hidden matter, such as secret corruption, or if the testimony was contested, such as testifying with two slaves or a single witness, and it was rejected for that reason, or if it was dead or absent, it is possible that he may have recourse, because he paid with legal evidence, and the determination of status (al-jarh wa al-taʿdil) is not his affair. It is also possible that he may not have recourse, because he brought as witnesses those whose testimony does not establish the right. If he paid without evidence in the presence (25) of the guaranteed party, there are two opinions: one is that he has recourse. This is the school of Al-Shafiʿi, because when he is present, the responsibility for caution lies with him, so if he fails to secure himself while he is present, he is the one who is negligent, not the guarantor. The second is that he has no recourse, because he made a payment that does not exonerate, so it is similar to the case where he paid in his absence. Now, if (26) he has recourse...