Dear respected Shaykh, assalamu alaikum wa rahmatullahi wa barakatuh. What is the authenticity of the hadith that the Prophet (peace be upon him) supplicated against a person who ate with his left hand after he ordered him to eat with his right hand, and he said, “I cannot do that”. Then the Prophet (peace be upon him said, "May you not be able to do that." ما صحة حديث ((كل بيمينك

Praise be to Allah, and may Allah’s peace and blessings be upon the Messenger of Allah, his family and his companions. Wa alaikum assalam wa rahmatullahi wa barakatuh. As to what follows: In response to your question, we say:   The hadith is  Sahih Muslim (2012) and it was narrated by Salamah ibn al-Akwa’ and its wording is, “A man ate with his left hand in the presence of Messenger of Allah (peace be upon him), whereupon he said, "Eat with your right hand." The man said: "I cannot do that." Thereupon he (the Prophet (peace be upon him) said, "May you not be able to do that." It was vanity that prevented him from doing it and he could not raise it (the right hand) up to his mouth afterwards.” And Allah knows best.