Chapter 4, Mishnah 6, is the final Mishnah of the chapter, and also the final Mishnah of the four chapters we have been studying that discuss the thoughts a person has during the offering of a sacrifice. Until now, we have dealt with invalidating thoughts and the problems they can cause; here, the Mishnah turns to the opposite side: what a person must intend lechatchilah (ideally). The Mishnah lists six intentions, and none of them are absolute requirements, meaning that bedieved (after the fact), their absence does not invalidate the sacrifice. The invalidating thoughts are specifically thoughts of outside its proper time and outside its proper place, as well as, for a Chatas or a Pesach in its proper time, the intention for the wrong type of sacrifice or the wrong person.
The six intentions that one must have lechatchilah:
"Leshem zevach" - intention for the specific type of sacrifice: if it is an Olah, one must intend it for the sake of an Olah, and similarly for the other sacrifices. This intention is incumbent upon the person performing the service, doing the slaughtering, receiving the blood, and the rest of the services.
"Leshem zoveach" - intention for the person bringing the sacrifice to be offered, the owner of the Olah, Shelamim, or Chatas.
"Leshem Hashem" - intention that the sacrifice is being offered to Hashem. "Hashem" here refers to the four-letter Name of God, which expresses the fact that the Almighty is completely exalted above space and time: the Creator and Sustainer of the world, and therefore He is outside the physical world and does not need this sacrifice in any way. There is no concept here, God forbid, of feeding Him, as it were, but rather a specific understanding of God as exalted and elevated.
"Leshem ishim" - that he should have in mind that the sacrifice will be properly burned on the altar: in all sacrifices, this refers to the eimurim, the parts offered on the altar, and in an Olah, to the entire meat. Lechatchilah, one must intend that the meat turn to smoke and not just remain on the fire.
"Leshem rei'ach" - that he should have in mind that the burning will produce, as it were, a scent from the burning meat. This is a separate matter in its own right.
"Leshem nicho'ach" - that he should have in mind that this will bring satisfaction before the Almighty, as it were: that He gave the commandment and man fulfilled it, which brings satisfaction Above.
For a Chatas sacrifice, a seventh intention is added: for the sake of the specific sin for which the animal is brought.
As we have already learned, the lack of intention for the type of sacrifice or for the person bringing it does not invalidate the sacrifice, and even intention for the wrong type or the wrong person does not invalidate it; rather, the one who brings it does not fulfill his obligation with it and must bring another sacrifice. These are two separate matters, and we already discussed them at the beginning of the tractate. The exceptions are the Chatas and the Pesach in its proper time, where intention for the wrong type of sacrifice or the wrong person actually invalidates them.
The source of the intentions:
Five of the six intentions are actually derived from a single verse dealing with the Olah sacrifice, where it is stated that the kohen shall burn it all on the altar:
"Olah" - leshem zevach, the correct type of sacrifice.
"Isheh" - leshem ishim, the burning.
"Rei'ach" - the pleasant scent.
"Nicho'ach" - the satisfaction.
"La'Shem" - leshem Hashem.
Although these are the sources of the obligations from the Torah, as mentioned, these intentions are not absolute requirements.
The stipulation of Beis Din:
The Mishnah adds, and these are the words of Rabbi Yosi, that if he did not have any of these things in his heart, it is valid bedieved. The Gemara explains that Rabbi Yosi does not argue on this, and brings a proof for the matter: it is a stipulation of Beis Din. The Sanhedrin stipulated that the kohen does not need to have in mind the identity of the owner or the type of sacrifice during the slaughtering, the receiving, and the rest of the blood services; rather, a general intention is sufficient: for the sake of whoever brought it, and for the sake of the sacrifice that it truly is.
And the reason for the stipulation: the Sages worried about mistakes. With many people, many animals that look alike, and abundant work - a slight lapse of attention is enough for the thought to fall on the wrong type of sacrifice, and it would turn out that the owner does not fulfill his obligation. This would cause great embarrassment, and therefore the Sanhedrin stipulated that the kohanim should process the sacrifices with this general intention, and through this the owners fulfill their obligation.
We also learn from here: Even though the verse lists these intentions, the fact that the Beis Din had the authority to stipulate that one can offer a sacrifice without explicit intention and still fulfill the obligation clearly proves that the lack of intention does not invalidate it on a Torah level. If it did, the Sanhedrin would not have the power to make such a stipulation. Thus, all six intentions mentioned in the Mishnah are required only ideally (lechatchilah), but do not invalidate the sacrifice after the fact (bedieved).
"Ein hamachashavah holeches ela achar ha'oved" - The intention follows only the one performing the service:
Rabbi Yosi further states that regarding intention, we only consider the person actually performing the service: the slaughtering, the receiving of the blood, the burning of the sacrificial parts for a pleasing aroma, and so forth. However, regarding the owner bringing the sacrifice, even if he had the correct intentions - it makes no practical difference, and likewise if he had improper intentions - it means nothing. The determining factor is specifically the one performing the service. In general, he does not need to have intention for a specific person or a specific type of sacrifice, but ideally, he must have intention for the other four components: for the sake of Hashem, for the sake of the fire, for the sake of the aroma, and for the sake of it being pleasing.
In summary: In this Mishnah, which concludes the chapter and the series of chapters dealing with intentions during sacrifices, we learned the six intentions one must have ideally - for the sake of the sacrifice, for the sake of the one sacrificing, for the sake of Hashem, for the sake of the fire, for the sake of the aroma, and for the sake of it being pleasing, and in the case of a sin-offering, also for the sake of the sin - and their source in the verse regarding a burnt-offering. We established that these intentions are not indispensable, and noted the stipulation of the Beis Din that proves this, as well as the rule that the intention follows only the one performing the service and not the owner.