[In this Chapter, we] shall Explain [Concerning] the Great Punishment [that befalls] one who Disputes [the teachings of] his Rabbi
Behold, the sin of strife even applies if someone argues with [a person] of equal stature. How much more so [does the sin of strife apply to] one who argues with a Torah scholar, even if [that scholar] is not his rabbi. All the more so, [the individual is guilty of the sin of strife] if it is his rabbi [with whom he argues], definitely his sin is great and [the] evil of his [action] is multiplied [in its intensity. The sin of strife is so severe, especially when one opposes a Torah scholar], for it is known that a quarrel involves shaming the opposing side with [one's] words. The greatness of the sin of one who scorns a Torah scholar is known from that which [our Sages of Blessed Memory have] said in [perek] Chelek, [Sanhedrin, 99b], and [this halacha has been] determined similarly in Yoreh Deah, in siman 243, sif 6, [where we learn] that one who scorns a Torah scholar is included among [those whom the pasuk refers to when it says], “For he has scorned the word of HaShem…, that soul shall surely be cut off, its sin is within it.” (Bamidbar: 15; 31) (In our times, even if [the individual] is only worthy to teach [Torah] and he has wearied himself in the Torah, he is called a “Talmid Chacham”. [Therefore], one who scorns [the Torah scholar], even only [by scorning him] with [his] words, and even [when he is] not present, it [nevertheless] is a criminal sin, and he is liable for excommunication because of this. [This follows that which is taught] in Yoreh Deah, in siman 243, sif 7, and in siman 334 in the Shach, sif kattan 68.) In addition, [one who scorns a Torah scholar] has no remedy for his infliction [which comes as a result] of this [sin], as is [taught in maseches] Shabbos (119b): “Rav Yihudah said in the name of Rav, ‘All those who scorn a Talmid Chacham have no remedy… Furthermore, the destruction of Jerusalem came about as a result of this sin [of scorning Torah scholars], as it says, “And they were mocking the messenger of G-d, and they were scorning His words, and were deceitful with His prophets, until the anger of HaShem arose in His nation, to the point of no remedy.”” (Divrei HaYomim II: 36; 16) [Our Sages of Blessed Memory have] also said in [maseches] Berachos (19a): “Rabbi Yihoshua ben Levi said, “all those who speak [that which is forbidden to speak against a Torah scholar], behind [the] coffin [of that Torah scholar], falls into gehinnom, as it says…”
 His rabbi refers to the rabbi from whom he learns or has learned Torah. The halacha is even stricter when one acts inappropriately in respect to the rabbi who has imparted the individual with most of his Torah wisdom. For example, it is forbidden to impart halachic rulings within a given proximity of the residence of his rabbi without being permitted. This law is stricter when it comes to the rabbi from whom he possesses most of his Torah knowledge.
 The gemara in maseches “Sanhedrin” (99a) quotes Rav and Rabbi Chaninah who list those who mock Torah scholars as apikorus’ (individual’s who are familiar with the Torah and reject it). The mishna on 90a lists apikorsim as among those individuals who do not receive a portion in The World to Come.
 This halacha in the Shulchan Aruch continues by teaching us that once the individual is placed in excommunication for scorning the Torah scholar. That excommunication is only reversed once the Torah scholar that he scorned is mollified. If the Torah scholar that he mocked had passed away, his state of excommunication is reversed by the Beis Din (Jewish religious court) upon his repentance.
 The full teaching from maseches “Berachos”, is as follows: “Rabbi Yihoshua ben Levi said, “all those who speak [that which is forbidden to speak against a Torah scholar], behind [the] coffin [of that Torah scholar], falls into gehinnom, as it says, “And those who turn themselves to perverseness, HaShem Will lead them with those who perform iniquity, peace upon Israel.” (Tehillim: 125; 5) Even at the time that there is peace upon Israel, HaShem Will lead them with the performers of iniquity.” RaSh”I points out that HaShem Will lead these individuals to gehinnom, along with the performers of iniquity.