He prohibited us from eating blood. And that is His saying, "And you shall not eat any blood" (Leviticus 6:26). And the prohibition about it has already been repeated [several] times. And the explanation that it is [punished] with excision which is in Scripture is His saying, "whoever eats it shall be excised" (Leviticus 17:14) - if it was volitional. But if inadvertent, he is liable for a fixed sin-offering. And the regulations of this commandment have already been explained in Chapter 5 of Keritot. (See Parashat Tzav; Mishneh Torah, Forbidden Foods 6.)