This is referring to a case where he intended both to extinguish and to kindle. The Torah singles out the labor of kindling on Shabbat, as it is written: “You shall not kindle fire in all your dwelling places on the day of Shabbat” (Exodus 35:3). The Sages disagree with regard to the interpretation of this verse. As the first tanna holds in accordance with the opinion of Rabbi Yosei, who says: Kindling was singled out from the general category of prohibited labors in order to teach that it is unlike other labors, teaching that it is a regular prohibition, i.e., it is punishable only with lashes and does not entail karet or stoning for an intentional transgression, or a sin offering for an unwitting transgression. Consequently, he is not liable to bring a sin offering for the kindling.

And Rabbi Eliezer, son of Rabbi Tzadok, holds in accordance with the opinion of Rabbi Natan, who says: Kindling was singled out in the Torah to divide the various primary categories of labor and to establish liability for the performance of each of them. According to this opinion, the prescribed punishments for kindling are the same as for the rest of the prohibited labors.

Rava said yet another explanation of the disagreement in the baraita: The difference between them involves a case where one intended to ignite the lower coals and subsequently extinguish the upper coals, and instead he extinguished the upper ones and ignited the lower ones simultaneously. Since he performed the extinguishing first and did not perform it after he ignited as he had intended, the first tanna rules he is liable to bring only one sin offering. By contrast, Rabbi Eliezer, son of Rabbi Tzadok, maintains there is no exemption for performing the prohibited labors in a different sequence than intended.

Rav Ashi said another explanation: The baraita is referring to a case where he intended to extinguish a flame and he was not aware that the bottom coals would be kindled. Rather, they ignited by themselves, as he moved aside and extinguished the upper coals. And the first tanna holds in accordance with the opinion of Rabbi Shimon, who says: If one commits an unintentional act, an action from which an unintended prohibited result ensues on Shabbat, as he did not intend to perform a prohibited labor, he is exempt. And Rabbi Eliezer, son of Rabbi Tzadok, holds in accordance with the opinion of Rabbi Yehuda, who says: One who commits an unintentional act from which a prohibited labor inadvertently results is liable.

The Sages taught in a baraita: Concerning one who stokes coals on Shabbat with the intention to move them in order to be warmed by them, and they ignited by themselves; it is taught in one baraita that he is liable and it is taught in another baraita that he is exempt. The Gemara explains: The reason for that which is taught in the first baraita, i.e., that he is liable, is that this tanna holds that one who performs a labor on Shabbat that is not necessary for its own sake, i.e., he performs the labor for a purpose other than the direct result of the action, is held liable for it. And the reason for that which is taught in the second baraita, i.e., that he is exempt, is that he holds that one who performs a labor that is not necessary for its own sake is exempt from liability for it.

MISHNA: If one consumed an olive-bulk of blood that spurted during the slaughter of a domesticated animal, an undomesticated animal, or a bird, whether it is a kosher or non-kosher species; or if one consumed blood that flowed after stabbing an animal or killing it in a manner other than by ritual slaughter, or blood that spurted after ripping the animal’s windpipe or gullet, or blood that spurted during bloodletting with which the soul departs, one is liable to receive karet for consuming it intentionally or to bring a sin offering for consuming it unwittingly.

But with regard to blood of the spleen, blood of the heart, blood of eggs, blood of grasshoppers, or blood of exudate [tamtzit], i.e., that oozes from the neck of the animal after the initial spurt of its slaughter concludes,one is not liable for consuming it. Rabbi Yehuda deems one liable in the case of blood of exudate.

GEMARA: The Sages taught in a baraita: The verse states: “And you shall consume no manner of blood” (Leviticus 7:26). I would derive from here that even with regard to the blood of bipeds, i.e., human beings, and the blood of eggs, the blood of grasshoppers, and the blood of fish, all these are included in the prohibition against consuming blood. Therefore, the verse states: “Whether it is of bird or of animal” (Leviticus 7:26).

The baraita explains the derivation from the verse: Just as birds and animals are unique in that they have the capacity for both a light form of ritual impurity, if they become impure after they are slaughtered, in which case they are considered impure food, and a severe form of impurity, if they die without valid ritual slaughter, and they have the possibility of being forbidden or permitted, and they are a type of meat, so too, everything that has the capacity for both a light form of impurity and a severe form of ritual impurity, and has the possibility of being forbidden or permitted, and is a type of meat, is included in the prohibition.

I will therefore exclude the blood of bipeds, as they have the capacity for a severe form of ritual impurity, i.e., the impurity of a corpse, but they do not have the capacity for a light form of ritual impurity, since the halakhot of the impurity of food do not apply to the human body.