(4) He is to lean his hand *lean his hand: The meaning of this act has puzzled commentators. It may symbolize ownership, a statement of the reason for the sacrifice, or perhaps identification with the animal (as a substitute for the life of the worshiper). on the head of the offering-up,

that there may be acceptance on his behalf, to effect-ransom *to effect-ransom: Heb. root k-p-r (again, see “On Translating Leviticus”). The aspect of “ransoming” mentioned here does not recur with the other sacrifices; some have postulated an original nonpriestly venue for this type of offering. for him. FOX

וסמך ידו, according to the plain meaning of the text, [this is not a commandment but the Torah describes the norm when people offer such an animal. It describes a preparatory activity, Ed]

The word “his hand” (yado) must be understood as referring to both hands. This is especially clear in light of the explicit verse later in Book of Leviticus 16:21, which states:

“And Aaron shall lay both his hands upon the head of the goat.”

Accordingly our sages established the rule (Menachot 93a):

“This serves as a general principle: wherever the Torah says ‘his hand,’ it means two hands.”

...

Further proof that the laying-on of hands was performed with both hands can be seen in the following verses:

Book of Leviticus 8:14, 8:18, and 8:22, where it states:

“They laid their hands.”

By contrast, there are places where only one hand is mentioned (Leviticus 8:24). Although several people are involved there, the expression used is still “their hand.”

Similarly in Book of Numbers 27:18, God tells Moses:

“And you shall lay your hand upon him. (Joshua)”

Yet when the act is actually carried out (27:23), the text reads:

“He laid his hands upon him.

The Gemara raises an objection to this from a baraita: “Speak to the children of [benei] Israel” (Leviticus 1:2). The word benei literally means: Sons of. And it states nearby: “And he shall place his hand on the head of the burnt-offering” (Leviticus 1:4), from which we learn that the sons of Israel place their hands, but the daughters of Israel do not place them.

Rabbi Yosei and Rabbi Yishmael say: It is optional for the daughters of Israel to place their hands. They may place their hands if they so choose, although they are not obligated to do so.

Rabbi Yosei said: The Sage Abba Elazar related to me the following incident: On one occasion, we had a calf for a peace-offering, and we brought it to the Women’s Courtyard, and women placed their hands on it. We did this not because there is an obligation of placing hands in the case of women, but in order to please the women, by allowing them to sacrifice an offering, in all of its particulars, as men do.

And so we find in the portion of Pinchas (Numbers 27:18) regarding Joshua, that the Holy One, blessed be He, said to Moses: Take for yourself Joshua son of Nun, a man who has spirit within him, and you shall lay your hand upon him — implying one hand. But in practice it is stated (Numbers 27:23): And he laid his hands upon him — implying two hands. Similarly here, in the command it says and he shall lay his hand, but in practice it is written: and Aaron shall lay both his hands. And likewise in the portion of Pinchas, the passage about the daily burnt offering is placed next to Joshua’s appointment, to tell you that just as the regular offerings bear the guilt of the people — and this is the reason for the laying of hands, to place the taint and blemish of all Israel upon the offering,

so too the leaders of Israel are a guilt offering for the people, as our Sages learned (Sifrei, Deuteronomy 1:13) from the verse and I will make them heads over you — that the guilt of the people is dependent on their leaders. ...

MISHNA: For all communal offerings there is no mitzva of placing hands on the head of the offering, except for the bull that comes to atone for a community-wide violation of any one of the mitzvot that was perpetrated due to an erroneous ruling of the Sanhedrin, where the judges of the Sanhedrin are required to place their hands upon its head (see Leviticus 4:13–21); and the scapegoat brought on Yom Kippur, upon which the High Priest places his hands (see Leviticus, chapter 16). Rabbi Shimon says: Also in the case of the goat that comes to atone for a community-wide perpetration of idol worship that occurred due to an erroneous ruling of the Sanhedrin, the judges of the Sanhedrin are required to place their hands upon its head (see Numbers 15:22–26).

(13)If it is the whole community of Israel that has erred and the matter escapes the notice of the congregation, so that they do any of the things that by GOD’s commandments ought not to be done, and they realize their guilt— (14) when the sin through which they incurred guilt becomes known, the congregation shall offer a bull of the herd as a purgation offering, and bring it before the Tent of Meeting. (15)The elders of the community shall lay their hands upon the head of the bull before GOD, and the bull shall be slaughtered before GOD.

(1) AND THE ELDERS OF THE CONGREGATION. The elders are the leaders. They will lay their hands on their behalf and on behalf of all of Israel, for it is impossible for all of Israel to place their hands.

(18) And GOD answered Moses, “Single out Joshua son of Nun, an inspired man, and lay your hand upon him. (19) Have him stand before Eleazar the priest and before the whole community, and commission him in their sight. (20) Invest him with some of your authority, so that the whole Israelite community may obey. (21) But he shall present himself to Eleazar the priest, who shall on his behalf seek the decision of the Urim before GOD. By such instruction they shall go out and by such instruction they shall come in, he and all the Israelites, and the whole community.” (22) Moses did as GOD commanded him. He took Joshua and had him stand before Eleazar the priest and before the whole community. (23) He laid his hands upon him and commissioned him—as GOD had spoken through Moses.

(1) Moses received the Torah at Sinai and transmitted it to Joshua, Joshua to the elders, and the elders to the prophets, and the prophets to the Men of the Great Assembly. They said three things: Be patient in [the administration of] justice, raise many disciples and make a fence round the Torah.

(2) Shimon the Righteous was one of the last of the men of the great assembly. He used to say: the world stands upon three things: the Torah, the Temple service, and the practice of acts of piety.

(3) Antigonus a man of Socho received [the oral tradition] from Shimon the Righteous. He used to say: do not be like servants who serve the master in the expectation of receiving a reward, but be like servants who serve the master without the expectation of receiving a reward, and let the fear of Heaven be upon you.

(4) Yose ben Yoezer (a man) of Zeredah and Yose ben Yohanan (a man) of Jerusalem received [the oral tradition] from them [i.e. Shimon the Righteous and Antigonus]. Yose ben Yoezer used to say: let thy house be a house of meeting for the Sages and sit in the very dust of their feet, and drink in their words with thirst.

Both the laying of hands by the Sages and the breaking of the heifer’s neck in a case where a person was found murdered and it is not known who killed him (see Deuteronomy 21:1–9) are performed in front of a panel of three judges;

§ The Sages taught in a baraita (Tosefta 10:15): The laying of hands and the laying of hands by the Sages are performed by three judges. What is the laying of hands, and what is the laying of hands by the Sages? It is clear that one of these terms is referring to the elders laying their hands on the bull offered for an unwitting communal sin, but what is the meaning of the other expression?

Rabbi Yoḥanan says: It is referring to the ordination of elders, meaning, to appoint Sages and grant them the title Rabbi.

at one time the wicked kingdom of Rome issued decrees of religious persecution against the Jewish people with the aim of abolishing the chain of ordination and the authority of the Sages. They said that anyone who ordains judges will be killed, and anyone who is ordained will be killed, and the city in which they ordain the judges will be destroyed, and the signs identifying the boundaries of the city in which they ordain judges will be uprooted. These measures were intended to discourage the Sages from performing or receiving ordination due to fear for the welfare of the local population.

§ Rabbi Yehoshua ben Levi says: There is no ordination outside of Eretz Yisrael. The Gemara asks: What is the meaning of: There is no ordination? If we say that they may not adjudicate cases involving laws of fines at all outside of Eretz Yisrael, that is difficult: Didn’t we learn in a mishna (Makkot 7a): The Sanhedrin and its authority functions both in Eretz Yisrael and outside of Eretz Yisrael? Rather, the intention is that we do not ordain judges outside of Eretz Yisrael.

At first, whoever, had received semichah would convey semichah on his students. Afterwards, as an expression of honor to Hillel, the elder, the Sages ordained that semichah would not be conveyed upon anyone unless license had been granted by the nasi.
They also ordained that the nasi should not convey semichah unless he is accompanied by the av beit din, and that the av beit din should not convey semichah unless he was accompanied by the nasi. The other elders could convey semichah themselves after receiving license from the nasi, provided they were accompanied by two others. For semichah cannot be conveyed by less than three judges.

If there was only one judge in Eretz Yisrael who possessed semichah, he should call two other judges to sit with him and they should convey semichah on 70 judges at one time or one after the other. Afterwards, he and these 70 should join together to make up the Supreme Sanhedrin and grant semichah to others to make up other courts.
It appears to me that if all the wise men in Eretz Yisrael agree to appoint judges and convey semichah upon them, the semichah is binding and these judges may adjudicate cases involving financial penalties and convey semichah upon others.
If so, why did the Sages suffer anguish over the institution of semichah, so that the judgment of cases involving financial penalties would not be nullified among the Jewish people? Because the Jewish people were dispersed, and it is impossible that all could agree. If, by contrast, there was a person who had received semichah from a person who had received semichah, he does not require the consent of all others. Instead, he may adjudicate cases involving financial penalties for everyone, for he received semichah from a court.
The question whether semichah can be renewed requires resolution.

Know that you must understand the following: anyone who wishes to uphold a particular opinion, to favor the person who said it, and to accept that opinion without examination or understanding—whether it is true or not—this is among the bad ways of thinking. It is forbidden both by the way of the Torah and by the way of reason.

It is not proper according to reason because it leads to deficiency and failure in examining what one ought to believe. And it is forbidden by the Torah because it turns a person away from the path of truth and from the straight line. As God said:

“You shall not show favoritism to the poor nor honor the great; with righteousness shall you judge…”

and

“You shall not show partiality in judgment.”

There is no difference between accepting an opinion without proof, and believing the one who stated it—showing him favor and claiming that the truth must certainly be with him merely because he is a great and trustworthy person. All of this is not evidence, and it is forbidden.

From this introduction it follows that, despite the great stature of the Sages of the Talmud and their perfection in explaining the Torah and its details, and their integrity in clarifying its general principles and particulars, we are not obligated to accept all of their statements in matters of medicine, natural science, and astronomy, nor to believe them in these matters in the same way that we believe them in the interpretation of the Torah—whose ultimate wisdom was placed in their hands and entrusted to them to teach to humanity, as it is said:

“According to the Torah which they shall teach you…”

You can see that the Sages themselves, when a matter had not been established through their reasoning and debate, would say:

“By God! Even if Joshua son of Nun had said this, we would not obey him.”

That is to say: we would not believe him—even though he was a prophet—because he does not possess the ability to clarify the matter through reasoning, argument, and the methods by which the Talmud is interpreted.

This alone is sufficient proof and demonstration.

Furthermore, we find that they themselves said that certain medical teachings mentioned in the Talmud were not confirmed, such as the remedy called tequmah, which they said could prevent miscarriage but which has not been verified. Many similar matters appear in the chapter “Eight Creeping Things” in Tractate Shabbat and elsewhere.

These were things that the Sages reported because they had been examined by investigators of their time and were accepted among people; therefore the Sages relied upon them. But they cannot be regarded as the established conclusions of a true physician nor as the result of demonstrative reasoning.