Sheikh Sulaymân al-Tuwayjirî
The left hand is used by a person to clean up filth, wash himself after going to the bathroom, and other similar activities. The right hand is used for clean practices like eating and shaking hands.
It is not permissible to eat with the left hand. Whoever does so has engaged in something unlawful and has committed a sin.
Once a man was eating in the company of the Prophet (peace be upon him) and was using his left hand. The Prophet (peace be upon him) said: “Eat with your right hand.”
The man responded: “I am not able to do so.” He only said this out of obstinacy.
So the Prophet (peace be upon him) said: “Then be unable to do so.”
The narrator of this hadîth then adds: “He was not able after that to raise his right hand to his mouth.” [Sahîh Muslim (2021)]
The Prophet (peace be upon him) said: “If one of you eats, he should eat with his right hand. And if he drinks something, he should drink with his right hand. For indeed, Satan eats and drinks with his left hand.” [Sahîh Muslim (2020)]
When `Umar b. Abî Salamah was a boy, he ate in the Prophet’s company, his had went all over the table setting, grabbing from here and there. The Prophet (peace be upon him) said to him: “My child, invoke Allah’s name, eat with your right hand, and eat from what is in front of you.” [Sahîh al-Bukhârî (5376) and Sahîh Muslim (2022)]
Therefore, a person must give preference to his right hand while eating. No one should eschew giving preference to his right hand unless that person has suffered the loss of his right hand or suffers from some genuine affliction that makes using the right hand truly difficulty.
It is not a legitimate excuse for someone who has no injury to the right hand to merely claims that he has tired to eat with his right hand but finds it difficult to do so. A Muslim is obligated to put the teachings of Islam into practice and not be neglectful of them.
It is alright for a person to use the left hand for other activities like physical work, cleaning, cooking, writing, and the like.
Source: Islam Today