What is the meaning of "ha'Oshek Yeholel Chacham"?
Rashi 1 : When a Kesil bickers with a Chacham, he confuses his Da'as 2 , and also he stumbles. Dasan and Aviram confronted Moshe, and said "Yere Hashem Aleichem v'Yishpot" (Shemos 5:21), and confounded him and made him lose his heart. This caused him to be adamant towards Hashem, and say "v'Hatzel Lo Hitzalta" (ibid. 23). He was punished for this - "Atah Sir'eh" (ibid. 6:1) - [you will see what I do to Pharaoh, but] you will not see the war against the 31 kings [in Eretz Yisrael]. Oshek is quarrel.
Ibn Ezra: It already said that a Chacham should not engage in laughter ("Lev Chachamim b'Veis Evel v'Lev Kesilim b'Veis Simchah" - 4).
Rashbam: This refers to "v'Lev Kesilim b'Veis Simchah" (4). Kesilim are drawn and avidly pursue Beis ha'Simchah. The Simchah leads them to sin. Therefore, Chachamim must distance from Kesilim. A Kesil, who is full of folly and quarrels, will make the Chacham a Kesil. The Kesil is called Oshek, for he is full of folly and Oshek (quarrels), just like "v'Chatas Amecha" (Shemos 5:16) - the nation is called Chatas.
Ri Kara: This explains "Tov Lishmo'a Ga'aras Chacham" (5). If a person abandons a trade, and oppresses and steals from the poor, sometimes he comes to a Chacham and the Chacham rebukes him - retract from your evil way, and adopt your initial trade. Oshek (oppression) makes a Chacham forget the trade that he had before becoming a robber.
Rid: [Even] if one is a great Chacham, and he engages in unjust gain, the money that he takes will transform him to be a lunatic - "Ki ha'Shochad Ye'aver Einei Chachamim" (Devarim 16:19).
R. Avigdor #1: Quarrels 3 that a Talmid makes with his Rebbi, they make him lose his Chachmah. Anyone who taught to him Mikra, Mishnah, Talmud, Halachos or Agados, even one Perek or one Halachah, is called his Rebbi, like we find with David (Avos 6:3).
R. Avigdor #2: We read Oshek like Osek (with a Samach). Shlomo was a great Chacham, and he engaged in matters, like the Gemara 4 says "Lech El Nemalah Atzel" (Mishlei 6:6). This makes a Chacham foolish - Shlomo relied on his Chachmah, and transgressed increasing wives, horses and money. Therefore, his wives veered his heart (Melachim I, 11:4) and he was deposed from his kingship for three years.
Seforno: Time that one 'steals' from investigation to jest about idle matters, it makes him foolish, for he neglects investigation.
Metzudas David: Even if the Chacham will rebuke Kesilim when he hears them speak light-headedness, it is not good to hear them, for when he rebukes them, they will reply to contest him, and confuse the Chacham's Da'as and make him lose his heart of Chachmah. Therefore, one should distance from them.
Rashi: There are other ways to explain, but they separate the verses from each other, and the Reisha of our verse proves that it is connected to the previous verse.
Metzudas Tziyon: Yeholel is confusing Da'as, like "v'Shoftim Yeholel" (Iyov 12:17).
Metzudas Tziyon: Oshek is quarrels, like "Es Kol ha'Ashukim" (4:1).
Magihah (in Toras Chayim): Chulin 57b says that R. Shimon ben Chalafta engaged in matters to see how Shlomo know this. R. Avigdor infers that also Shlomo did so.
Why does it say "vi'Yabed Es Lev Matanah"?
Rashi: It is a heart of Chachmah, which is a gift to man - "Ki Hashem Yiten Chachmah" (Mishlei 2:6).
Ibn Ezra: It says vi'Yabed (masculine) because it refers to Davar Matanah; the word Devar is omitted 1 . This is like "v'Sonei Matanos Yichyeh" (Mishlei 15:27).
Ri Kara: He loses the Chachmah that Hashem put in his heart. Since he engages in extortion, he forgets [Chachmah].
Rid: The gift (bribe) that the Chacham takes makes his lose his heart, Since a small [gift] can annul Chachmah and make it lost, this shows that also Chachmah is Hevel!
Seforno: Sometimes he will err about axioms that nature gave to him for a gift, without his efforts.
Ibn Ezra: Also "Ad Nimtza Avlasah Vach" (Yechezkel 28:15, it is as if it says Devar Avlasah).
