The ruling on repeating the prayer when one forgets a state of ritual impurity or the presence of impurity

Question:
May Allah reward you. Honorable Shaykh, this questioner says: If a person becomes in a state of ritual impurity and prays while forgetting, then remembers, he repeats the prayer. But if there is impurity on his garment and he prays while forgetting, he does not repeat the prayer. The question is: why does he repeat it in the first case but not in the second?

Answer:
Because the Prophet (peace and blessings be upon him) prayed wearing his leather socks, and during the prayer he took them off. When he finished the prayer, he informed his Companions that he had taken them off because Jibril had informed him that there was impurity in them. The fact that the Prophet (peace and blessings be upon him) continued his prayer and did not repeat it is evidence that if one prays while having a garment with impurity on it, forgetting it, his prayer is valid. This is because the Messenger (peace and blessings be upon him) continued from the beginning of the prayer, even though he was wearing footwear that contained impurity.