In case it is a chieftain who incurs guilt by doing unwittingly any of the things which by the commandment of his God יהוה ought not to be done, and he realizes guilt—
אשר נשיא יחטא — The word אשר is connected in meaning with אשרי “happy”. Happy is the generation whose prince (king) takes care to bring an atonement sacrifice even for an inadvertent act of his; how much the more certain is it that he will do penance for his wilful sins (Sifra, Vayikra Dibbura d'Chovah, Section 5 1; Horayot 10b)
MISHNA: If a king or High Priest sinned before they were appointed, and thereafter they were appointed, the status of these people is like that of commoners; they bring the sin-offering of an individual. Rabbi Shimon says: If it became known to them, before they were appointed as king or High Priest, that they had sinned, they are liable to bring the sin-offering of an individual, but if it became known to them after they were appointed as king or High Priest they are completely exempt.
Who is the nasi? This is a king, as it is stated: “When a nasi sins, and performs any one of all the mitzvot of the Lord his God that shall not be performed, unwittingly, and he is guilty” (Leviticus 4:22), referring to one who has only the Lord his God over him and no other authority. That is only the king.
§ Apropos a king, the Sages taught: In contrast to other cases where the verse states: If he will sin, it states concerning a king: “When [asher] a king sins.” One might have thought that this is a decree, i.e., that it is a given that the king will sin. Therefore, the verse states: “If the anointed priest shall sin” (Leviticus 4:3). Just as there the meaning is: In the event that the priest shall sin, so too here, the meaning is: In the event that the king shall sin.
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The Gemara analyzes the baraita. The Master said: One might have thought that this is a decree. The Gemara asks: A decree? From where would this be derived? Why would it enter one’s mind that there would be a decree that the king must sin?
The Sages say: Yes, there is a basis for that understanding, as we find that type of interpretation elsewhere; as it is written: “When you come into the land of Canaan, which I give to you for a possession, and I shall place the mark of leprosy in a house of the land of your possession” (Leviticus 14:34). These are tidings informing them, i.e., the Jewish people, that leprous marks will come upon them when they enter Eretz Yisrael; this is the statement of Rabbi Yehuda. Rabbi Shimon says: This verse serves to teach that leprosy causes ritual impurity only when its origins are divine, to the exclusion of leprosy that results from circumstances beyond one’s control, i.e., those that have a clear physical cause. Didn’t Rabbi Yehuda say that leprosy could be tidings, i.e., that there will definitely be leprosy? Here too, with regard to the king, say that it is a decree that he will sin. Therefore, it is written: “If the anointed priest shall sin,” meaning that the sin is not a given.
§ The Sages taught: The verse states concerning a king: “When [asher] a king sins” (Leviticus 4:22). Rabbi Yoḥanan ben Zakkai said: Happy [ashrei] is the generation whose king feels the need to bring an offering for his unwitting transgression. If the generation’s king brings an offering, you must say all the more so what a commoner will do to atone for his sin, i.e., he will certainly bring an offering. And if the king brings an offering for his unwitting transgression, you must say all the more so what he will do to atone for his intentional transgression, i.e., he will certainly repent.
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אשר נשיא יחטא, when the King (or political head) sins; there is no conditional word אם, “if,” i.e. the Torah considers it as almost a given that the political head of the people will become guilty of at least an inadvertent sin. Moses describes such a likely scenario as the result of the people enjoying good times, when he says in Deuteronomy 32,15 וישמן ישורון ויבעט, “when Yeshurun waxed fat it kicked. ואשם, he realised himself that he had sinned; it did not have to be brought to his attention by others. או הודע לו, or his sin had to be brought to his attention by others. The vowel cholem on the letter vav substitutes for the vowel shuruk which would have made it clear that it is a passive mode.
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WHEN A RULER SINNETH, ETC. R. Isaac pointed out that the corresponding clauses referring to the high priest and the congregation begin with the word “if,-“if the anointed priest shall sin, etc.” (Lev. 4, 3). “if the whole congregation of Israel shall err, etc.” (Ibid. 13).
The reason is’, he said, ‘that it is exceptional for the High Priest to sin, since he feels his responsibility to his Master and to Israel and to each individual. Similarly, it is very exceptional for the whole congregation to commit one and the same sin, for if some commit it, others will not. But a prince’s heart is uplifted because of his power, and therefore he is almost bound to sin; hence it says here, “when”, and not “if’.’
Alternatively, we could understand the word to reflect a definitive statement, i.e. the Torah assuming that at one point or another a king is going to commit a sin and will have to offer a sin-offering. This then would account for the fact that the Torah did not choose to write אם נשיא יחטא, “if a king will sin, etc.” Seeing that the Torah had written אם הכהן המשיח יחטא, “if the High Priest will sin,” and it had written ואם כל עדת ישראל ישגו, “and if the entire congregation of Israel err, etc.,” the reason could be that seeing the High Priest is so careful not to sin, and the entire High Court cannot be presumed to err, the Torah did not want to write the word אשר in those instances which would have made a flat statement that these representatives of the people who are imbued with Holy Spirit would commit inadvertent sins. A king, who is no religious authority and to whom neither the people’s purity nor their piety is directly entrusted, is much more likely to err and sin; therefore the Torah used the expression אשר, to indicate that the Torah considers the fact that a king will sin at one time or another as a given. Kings have a hard time combating their arrogance and it is therefore not unusual for them to become guilty of sins. Keeping the pressures on kings to combat their egos in mind, the Torah devoted several verses to this in Deut. 17,20 and legislated certain restrictions on them to restrain their feeling all-powerful and above the law
It was not accidental that the princes- the nearest thing to kings the Israelites had in those days- donated the precious stones for the shoulder piece and breastplate of the High Priest as they were to atone for the sin of arrogance. Compare what we wrote on Exodus 35,27.
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