Sifrei Devarim 76/ספרי דברים ע״ו

32. R. Shimon says:Every commandment which Israel receivedin joy from Mt. Sinai,they now perform with joy;but every commandment which Israel did not receivein joy from Mt. Sinai,they do not perform with joy!Rabban Shimon b. Gamliel says:Every commandment for whichIsrael martyred itself in times of persecution,they now practice openly;but every commandment for whichIsrael did not martyr itself in times of persecution,still wavers in their hands!

4“For the blood is the vital-force” (Dt. 12:23)—this explains the point [of not eating the blood].

53. “So, do not eat the vital-force with the meat” (Dt. 12:23).This verse [proscribes] eatinga limb cut from a living animal.Now, doesn’t reason dictate as much?Just as a mixture of milk and meatis permitted to descendants of Noah,but prohibited to Israel,isn’t it reasonable thata limb cut from a living animal,which is prohibited to descendants of Noah,should be prohibited to Israel as well?[The example of] the shapely war-captive (Dt. 21:11)—and other similar cases—illustrates the issue.For she is prohibited to descendants of Noah,but permitted to Israel!Thus, you should not wonder whya limb cut from a living animal—while it is prohibited to descendants of Noah—might be permitted to Israel![Therefore,] the Teaching states:“So, do not eat the vital-force with the meat” (Dt. 12:23)—This verse [proscribes] eatinga limb cut from a living animal.

8R. Eliezer says:Now, just as the Paschal lamb,for the boiling of which we are not held liable,yet, we are held liablefor eating [the boiled meat],so, too, a mixture of milk and meat,for the boiling of which we are held liable—isn’t it reasonable that we beheld liable for eating it as well?The example of compounding incenseillustrates the issue.For we are held liablefor [an error] in compounding [the ingredients],but are not held liable for sniffing it!Thus, you should not wonder whya mixture of milk and meat—although we are held liable for boiling it,we might not be held liable for eating it![Therefore,] the Teaching states:“Do not eat it” (Dt. 12:24)—this includes [the proscription against eating]a mixture of milk and meat.