What specifically was the sin of Acher (Elisha ben Avuyah)?

Question

In Chagigah 14b-15a it says

What is the meaning of "Acher destroyed the plants"? Of him scripture says: "Do not let your mouth make your flesh sin". What does this mean? Acher saw that Metatron happened to be granted authority to sit while he record the merits of Israel, and he said: "We have been taught that in heaven there is no sitting.... Perhaps there are — God forbid! — two supreme powers". They brought him to Metatron and they smote him with sixty bands of fire. They said to Metatron: "When you saw him, why did you not stand up before him?" Then authority was granted Metatron to erase the merits of Acher. Then a heavenly voice was heard: "'Repent, O backsliding children!' except for Acher."

What exactly (i.e which of the 613 mitzvot) was violated? Is the belief in shtei reshuiot part of the transgression of having other gods?

Answer 1

קיצץ נטיעות: פירש הערוך דיבר כלפי מעלה

Destroy the plants

Gemara 15a:

1. First error: doubt about two powers

אחר קיצץ בנטיעות, עליו הכתוב אומר (קהלת ה') אל תתן את פיך לחטיא את בשרך. מאי היא? חזא מטטרון דאתיהבא ליה רשותא למיתב למיכתב זכוותא דישראל, אמר: גמירא דלמעלה לא הוי לא ישיבה ולא תחרות ולא עורף ולא עיפוי, שמא חס ושלום שתי רשויות הן. ‏

The Gemara told how he seen Matat' who decide in high tribunal, not G-d himself. This discovery was contradictory to the principles which he previously learned. The expression kitsets netiot is explained by Rabbi Yaakov Kapil Lifshits in Shaare Gan Eden, cuting the roots of a tree is an alegory. This means to separate a consequence (a branch) from its cause (the root), and to make them two independent being. The cause is Hashem, the consequence is a "spiritual product".

At this stage he was breaking the first Negative Mitsva (Lo Taasse 1, Rambam Sefer Hamitsvot), the second comendment :

הראשונה ממצוות לא תעשה היא האזהרה שהוזהרנו מלהאמין [וליחס] אלהות לזולתו יתעלה. והוא אמרו- יתרומם מליחס לו אמירה -: "לא יהיה לך אלהים אחרים על פני" (שמות כ, ג). וכבר נתבאר בסוף מכות שלאו זה הוא מכלל תרי"ג מצוות, והוא אמרם שם: "שש מאות ושלש עשרה מצוות נאמרו לו למשה בסיני וגו'". כמו שביארנו במצווה הראשונה ממצוות עשה.

The prohibition to believe that there is divinity out of G-d.

2. Rectification: Experimental proof that Matat' has no own power.

אפקוהו למטטרון ומחיוהו שיתין פולסי דנורא. אמרו ליה: מאי טעמא כי חזיתיה לא קמת מקמיה? ‏

The Gemara told us that they showed him that Matat' is not the chief and they mistreating Matat', thy did beaten him.

3. Second mistake, renouncing to the option of repentence:

איתיהיבא ליה רשותא למימחק זכוותא דאחר, יצתה בת קול ואמרה (ירמיהו ג') שובו בנים שובבים - חוץ מאחר, אמר: הואיל ואיטריד ההוא גברא מההוא עלמא ליפוק ליתהני בהאי עלמא. נפק אחר לתרבות רעה. ‏

After this Matat' went to take revenge. The second mistake of EBA was that he finally accepted the sentence of Matat' who declared the Impossibility to make Teshuva for EBA. EBA so decided to search pleasure in This world only..

The sefer Hayikarim, in maamar 1, chapter 2 learns from our gemara the Talmud of Jerusalem ( Chagiga 9ab) a principle concerning the question who is heretic. The statement quoted in the Yikarim is:

"Everybody can return to teshuva excepted Elisha {called} "one Other" who knows his Creator and rebelled against Him intentionally". The Ikarim deducted that an error occured in Torah learning doesn't make the student an heretic, even if the idea is heretical. An intentional rebelion was the sin of EBA. So it seems that at end, EBA did not be apikoros concerning the "two powers" hypothesis.

.

In conclusion EBA was initially wrong or at least sceptic and corrected his mistake but become wrong again, concerning his Teshuva option.

This was the last mistake.. This passage of Talmud of Jerusalem is partially quoted in the Tosfot Chagiga 15a, and continues saying that EBA was a killer of Talmide Chachamim (I ask myself if we need to understand this concretly) and its problem was infringement. He was obviously 613ly spoken not a Tsadik.

So, EBA was mezid (at least at the last step) and disagree with Torah.The problem was not his first mistake in Torah learning. But his belief of the statement of Matatron (contrarilly to Eliezer Ben Dordea who heard the same sentence and despite that made teshuva and get in Olam Haba).

See also More Nevuchim 1, 32. It seems there that EBA learned a far too deep and hard topic and infered false conclusions. The Moreh explains that he became confused and made a mistake logical inferences. This describes the first error which generated the process. {We can perhaps infer that this paragraph in Moreh illustrate his disagrement to the Yikarim novelty.}

Summary, EBA made an error, unintentionally, at begining, there was no problem of 613. Further EBA neglected his duties intentionally. The first error started the process.. 613ly speaking, he committed crimes and several averot. A wrong belief generated by an error in learning Torah is not a sign of minut according to Ikarim and Raavad.