R' Shimon ben Menasya says: What is [referred to as] a twisted thing cannot be made straight? One who has an illicit relation-ship and begets a mamzer. Were you to say that [the reference is to] one who steals or robs [this could not be the meaning since] he can make restitution and [thus] make it straight.  R' Shimon ben Yochai says: We do not call one twisted unless he was initially straight and then became twisted. And who is this? This is a scholar who forsakes the Torah.

[The regulations governing] release from vows hover in the air and have no [firm Scriptural] support. [Certain] laws of the Sabbath, chagigah, and me'ilah are like mountains suspended by a hair, for there are few Scriptural references and many laws. [The regulations governing] property law, the [sacrificial] services, purity and contamination, and illicit relationships have [firm Scriptural] support. All of these are essentials of the Torah.

We may expound neither on [the subject of] illicit relationships to [a group of] three, nor on the account of the Creation to [a group of] two, nor on [the account of] the Merkavah to an individual unless he is wise and understanding through his own knowledge.  Whoever speculates on four things, it would be better for him had he not come into the world: What is above, what is below, what was before, and what will be after.  Similarly, whoever has no regard for the honor of his Maker, it would be better for him had he not come into the world.

Yose ben Yoezer says not to lean [the hands on the head of a sacrificial animal on Yom Tov]; Yose ben Yochanan says to lean. Yehoshua ben Perachiah says not to lean; Nittai the Arbelite says to lean. Yehudah ben Tabbai says not to lean; Shimon ben Shatach says to lean. Shemaiah says to lean; Avtalyon says not to lean. Hillel and Menachem did not disagree. Menachem left [office]; Shammai entered. Shammai says not to lean; Hillel says to lean.  The former [of the respective pairs] were Nesi'im; the latter were heads of the Beis Din.