In his final disease, the Prophet (s) asked people to retaliate upon him if he had made mistake with any of them intentionally or unintentionally. 
Suwada ibn Qays said: “God’s Messenger, once, you were riding your she-camel and having a cane in the hand when I received you after you had been in Ta’if. As you were trying to beat your riding animal with your cane, you hit my belly.” The Prophet (s) ordered him to retaliate. “Show me your belly,” asked Suwada, and the Prophet did. “May I put my mouth on your belly, God’s Messenger?” asked Suwada. The Prophet permitted, and Suwada said: “I seek the guard of the Prophet’s place of retaliation against fire of Hell.”
The Prophet then asked him to retaliate or forgive. “I will certainly forgive, God’s Messenger,” said Suwada. The Prophet prayed: “Allah, forgive Suwada ibn Qays, for he forgave You Prophet Mohammed.” ( Safinat ul-Bihar; part 1 page 671 ) 

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