One who learns from his fellow one chapter, or one halakhah, or one verse, or one word, or even one letter, is obligated to treat him with honor; for so we find with David, king of Israel, who learned from Ahitophel no more than two things, yet called him his master, his guide and his beloved friend, as it is said, “But it was you, a man mine equal, my guide and my beloved friend” (Psalms 55:14). Is this not [an instance of the argument] “from the less to the greater” (kal vehomer)? If David, king of Israel who learned from Ahitophel no more than two things, nevertheless called him his master, his guide and his beloved friend; then in the case of one who learns from his fellow one chapter, or one halakhah, or one verse, or one word, or even one letter, all the more so he is under obligation to treat him with honor. And “honor’” means nothing but Torah, as it is said, “It is honor that sages inherit” (Proverbs 3:35). “And the perfect shall inherit good” (Proverbs 28:10), and “good” means nothing but Torah, as it is said, “For I give you good instruction; do not forsake my Torah” (Proverbs 4:2). This mishnah teaches that one who learns even the smallest amount of Torah from someone else, must treat him with honor. This lesson is learned from King David’s treatment of Ahitophel. Ahitophel was David’s adviser, who betrayed him when Absalom, David’s son rebelled and claimed the kingship (See II Samuel 15:12). When Absalom did not take his advice to immediately wage war on David, Ahitophel committed suicide (17:23). According to rabbinic aggadah (legend), Ahitophel was a great sage, but came to an dishonorable end due to his excessive honor. Psalms 55:13-15 is understood as being a lament by David referring to Ahitophel (this is even how the ancient Aramaic translation, targum, translates the verse). David refers to Ahitophel with three titles of respect, due to the mere two things that Ahitophel taught him. According to various legends found in rabbinic literature these two things are: 1) That the Levites should carry the ark on their shoulders and not on a cart (see II Samuel 6:3-8); 2) That he could write the name of God on a piece of clay in order to prevent the primal waters from rising (this is a legend found in Sukkah 53b). If David, King of Israel treated Ahitophel, who only taught him these two things, with such honor, all the more so must a normal person treat those from whom he learns with respect. The mishnah ends with two midrashim. The first teaches that honor is equated with Torah and the second teaches that goodness is also equated with Torah. Keep in mind that this whole chapter is about the supreme value of the Torah.