Little is known of Elisha's youth and of his activity as a teacher of Jewish Law. He was the son of a rich and well-respected citizen of Jerusalem, and was trained for the career of a scholar. The only saying of his recorded in the Mishnah is his praise of education: "Learning Torah as a child is like writing on fresh paper, but learning Torah in old age is like writing on a palimpsest." (Avot 4:20). Other sayings attributed to Elisha indicate that he stressed mitzvot (good deeds) as equal in importance to education:
To whom may a man who has good deeds and has studied much Torah be compared? To a man who in building [lays] stones first [for a foundation] and then lays bricks [over them], so that however much water may collect at the side of the building, it will not wash away. Contrariwise, he who has no good deeds even though he has studied much Torah — to whom may he be compared? To a man who in building lays bricks first and then heaps stones over them, so that even if a little water collects, it at once undermines the structure.
Elisha was a student of Greek; as the Talmud expresses it, "Acher's tongue was never tired of singing Greek songs" (Jerusalem Talmud, Megillah i. 9). The Talmud suggests that his study of Greek philosophy was one of the factors that led him to apostasy (Hagigah 15b). Wilhelm Bacher, in his analysis of Talmudic legends, wrote that the similes attributed to Elisha (including the ones cited above) show that he was a man of the world, acquainted with wine, horses, and architecture. He evidently had a reputation as an authority in questions of religious practice, since Mo'ed Katan 20a records one of his halakhic decisions — the only one in his name, although others may be recorded under the names of his students or different rabbis. The Babylonian Talmud asserts that Elisha, while a teacher in the beth midrash (torah academy), kept forbidden books hidden in his clothes (Hagigah 15b).
One of the most striking references to Elisha is found in a legendary baraita about four rabbis of the Mishnaic period (first century CE) who visited the Orchard (that is, pardes or paradise) (Hebrew: פרדס orchard):
Four men entered the pardes — Ben Azzai, Ben Zoma, Acher [that is, Elisha], and Akiva. Ben Azzai looked and died; Ben Zoma looked and went mad; Acher destroyed the plants; Akiva entered in peace and departed in peace.
The Tosafot, medieval commentaries on the Talmud, say that the four sages "did not go up literally, but it appeared to them as if they went up." Ginzberg, on the other hand, writes that the journey to paradise "is to be taken literally and not allegorically"; "in a moment of ecstasy [Elisha] beheld the interior of heaven", but "he destroyed the plants of the heavenly garden".
The Talmud gives two different interpretations of this last phrase. The Babylonian Talmud 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."
Ginzberg comments that "the reference here to Metatron — a specifically Babylonian idea, which would probably be unknown to Palestinian rabbis even five hundred years after Elisha — robs the passage of all historical worth". Instead, he highlights the contrast between the accounts in the Babylonian Talmud and the Jerusalem Talmud, noting that the Jerusalem Talmud "makes no mention of Elisha's dualism; but it relates that in the critical period following the rebellion of Bar Kokba, Elisha visited the schools and attempted to entice the students from the study of the Torah, in order to direct their energies to some more practical occupation; and it is to him, therefore, that the verse 'Suffer not thy mouth to cause thy flesh to sin' is to be applied. In connection with this the Biblical quotation is quite intelligible, as according to another haggadah (Shabbat 32b; Ecclesiastes Rabbah 5:5) "flesh" here means children — spiritual children, pupils — whom Elisha killed with his mouth by luring them from the study of the Torah."
Others disagree with Ginzberg, suggesting that he failed to account for the regular travel of sages between Judea and Babylonia to collect and transmit scholarly teachings. Furthermore, scholar Hugh Odeberg has dated portions of the pseudepigraphal Third Book of Enoch, which discusses Metatron, to the first or second century CE, before the redaction of both the Jerusalem and the Babylonian Talmuds, and other scholars have found the concept of Metatron in texts older than 70 CE.
The Jewish Encyclopedia suggests that Elisha had become a Sadducee. It bases this on the fact that the Jerusalem Talmud mentions Elisha's betrayal of Pharisees. The Jewish Encyclopedia thus suggests that the antipathy of Elisha was not directed against all forms of Jewish worship existing at that time, but only against Pharisaism, despite the fact the sages who redacted the Jerusalem Talmud were Pharisees and may have simply focused on the betrayal against their own community. The Jewish Encyclopedia also suggests that one of the reasons given for Elisha's apostasy is characteristic of a Sadducee perspective. Elisha is said to have seen a child lose his life while fulfilling two laws for which the observance of the Torah promised a "long life" - honoring one's father and mother, and sending away a mother bird. whereas a man who broke the same law was not hurt in the least. This encounter, as well as the frightful sufferings of Jewish martyrs during the Hadrianic persecutions, led Elisha to the conclusion that there was no reward for virtue in this life, though the Pharisee sages interpreted this passage as referring to life and reward in the next world. Thus, the Jewish Encyclopedia suggests that Elisha was a Sadducee, since belief that reward and punishment must occur on Earth and disbelief in an afterlife are part of Sadducee philosophy. However, his abandonment of Jewish practice after his troubling encounters seems to indicate that, whatever his earlier philosophy, Elisha abandoned any form of Jewish religion.
The Jerusalem Talmud is also the authority for the statement that Elisha played the part of an informer during the Hadrianic persecutions, when the Jews were ordered to violate the laws of the Torah. As evidence of this it is related that when the Jews were ordered to do work on Shabbat, they tried to perform it in a way which could be considered as not profaning the Sabbath. But Elisha betrayed the Pharisees to the Roman authorities.
Medieval philosopher Rabbi Yehuda Halevi explained in his work The Kuzari that the heightened spiritual experience of "entering the Pardes" brought Elisha to belittle the importance of practical religious observance:
The third one [Elisha] fell into bad ways, because he viewed the spiritual entities and said, "These deeds are but tools and preparations to attain that spiritual level. Having already reached this level, I have no need for the Torah's commandments." He became corrupt and corrupted others; he went astray and caused others to go astray.
In his book, The Sinner and the Amnesiac: The Rabbinic Invention of Elisha Ben Abuya and Eleazar Ben Arach (2000), Rabbi Alon Goshen-Gottstein argues that rabbinic stories should be read as literature rather than as history:
They [the rabbis] construct stories that are then integrated into larger ideologically motivated literary units in such a way as to impart particular ideological messages. The sources do not necessarily relate the historical facts about the heroes but they do illustrate the cultural concerns that find expression in the stories told about them. ... All this leads to the realization that the significant unit for presentation is not the life of the sage; it is the stories about sages. These stories are not formulated in an attempt to tell the life of the sage. They are told because the sage, as part of the collective culture, has some bearing on the common cultural concerns. Various anecdotes are coupled into a larger story cycle.
Rabbinic Judaism was based on vigorous and often contentious debate over the meaning of the Torah and other sacred texts. One challenge facing the rabbis was to establish the degree of heterodoxy that was acceptable in debate. In this context, Elisha the heretic and Eleazar, who is said to have forgotten the Torah, represent two extremes in attitudes towards the Torah; actual rabbis and their arguments had to fit somewhere between these two limits.
The harsh treatment he received from the Pharisees was due to his having deserted their ranks at such a critical time. Quite in harmony with this supposition are the other sins laid to his charge; namely, that he rode in an ostentatious manner through the streets of Jerusalem on a Day of Atonement which fell upon a Sabbath, and that he was bold enough to overstep the "teḥum" (the limits of the Sabbath-day journey). Both the Jerusalem and the Babylonian Talmuds agree here, and cite this as proof that Elisha turned from Pharisaism to heresy. It was just such non-observance of customs that excited the anger of Akiva (Sotah 27b). The Jewish Encyclopedia writes that the mention of the "Holy of Holies" in this passage is not an anachronism, as Grätz thinks, for while it is true that Eliezer and Joshua were present as the geonim par excellence at Elisha's circumcision—which must, therefore, have occurred after the death of Johanan ben Zakkai (80)—it is also true that the "Holy of Holies" is likewise mentioned in connection with Rabbi Akiva (Makkot, end); indeed, the use of this expression is due to the fact that the Rabbis held holiness to be inherent in the place, not in the building (Yevamot 6b).
The same passage from the Jerusalem Talmud refers to Elisha as being alive when his pupil Rabbi Meir had become a renowned teacher. According to the assumption made above, he must have reached his seventieth year at that time. If Elisha were a Sadducee, the friendship constantly shown him by Rabbi Meïr could be understood. This friendship would have been impossible had Elisha been an apostate or a man of loose morals, as has been asserted. Sadducees and Pharisees, however, lived in friendly intercourse with one another (for example, Rabban Gamaliel with Sadducees; Eruvin 77b).
For legends concerning Elisha see Johanan ben Nappaha; Rabbi Meir; compare also Gnosticism.