What is the ruling of Sharia regarding someone who verbally attacks sheikhs and scholars in his lessons, making it clear that he is in the right?

Slandering scholars and diminishing their status is not permissible in Islamic law, due to the Prophet's (peace and blessings be upon him) saying: "He is not of us who does not respect our elders, show mercy to our youngsters, and acknowledge the right of our scholar." Imam Abu al-Qasim Ibn Asakir said: "The flesh of scholars is poisoned, and Allah's habit of exposing the veils of those who diminish them is well-known." However, clarifying a scholar's error while adhering to the etiquette of response is not blameworthy, because scholars refute one another. There is no one whose words are taken or left except the Messenger of Allah (peace and blessings be upon him). Therefore, scholars must be honored and revered, but the truth is more deserving of being followed, and an error is to be refuted to its proponent with adherence to the etiquette of response.