BLEEDING:
In accordance with the pathology of its epoch, the Talmud declares, "At the head of the list of human ailments stands plethora (B. B. 58b). The Rabbis say elsewhere (Bek. 44b), "Where there is an abundance of blood, there is also an abundance of eczema." Bloodletting is therefore considered of great importance; and the scholar is forbidden to reside at a place where no bloodletter ("uman," surgeon) is at hand (Sanh. 17b; Maimonides, "Yad," De'ot, iv. 23). The following are the rules, partly pathological and partly astrological or demonological, which the Rabbis recommend for the operation.
Necessity and Time of Operation.A man ought to be bled once every mouth, but with advancing years the intervals must be extended. The first, fourth, and sixth days of the week are the most appropriate for the operation. On the fourth day of the week, which falls on the fourth, fourteenth, or twenty-fourth of the month, or after which remain less than four days till the new moon, there must be no bloodletting, since at such times it is dangerous. On the first and second days of the month the operation is enervating, and on the third day dangerous. The operation is not permitted on the eve of a Biblical festival; neither must it be performed on a cloudy or a stormy day, or soon after eating a hearty meal, after partaking of cress, or while suffering with fever, while having sore eyes, or while exposed to a draft (Shab. 129a; Yeb. 72a; Ned. 54b; 'Ab. Zarah 29a). On entering the operating-room, the patient must offer the following prayer: "May it please Thee, O Lord my God! that this my project effect healing unto me; and do Thou heal me, for Thou, O God! art the true Physician, and Thy healing is true." After the operation one should say, "Blessed be the gratuitous Healer" (Ber. 60a; Maimonides, "Yad," Ber. x. 21.; Oraḥ Ḥayyim, 230, 4).
Dietary Rules After Operation.Immediately after the operation one should drink one-fourth of a log of red wine, as a substitute for the red blood lost. This is of so much importance that the very poor patient who can not buy the wine is permitted to obtain the prescribed quantity by calling at shops and tasting the wine, on pretense of intending to purchase a large supply. Or, failing in this, he must eat seven black dates, anoint his temples with oil, and then sun himself, in order to become thoroughly heated. Under ordinary circumstances, however, eating is to be deferred until such time has elapsed after which one can walk half a mile. A little rest after the operation is heartily recommended. Washing the hands is considered to be of almost equal importance, the omission of which will render the patient nervous for seven days (Shab. 129a; Pes. 112a; Oraḥ Ḥayyim, 4, 19). One must eat a good meal after the operation. So urgent are the Rabbis concerning this particular injunction that, although they have laid down the rule that a man should sell the roof of his house to buy himself shoes in case of necessity, they also prescribe that, if necessary, a man should sell his shoes in order to procure a good meal after bloodletting. Furthermore, they assert that the one who makes light of the meal on such an occasion will receive but slight sustenance from Heaven; if he does not prize his life, why should Heaven prize it? For this meal meat is recommended, or a dish of milt; but the flesh of fowls will produce palpitation of the heart. Fish is said to be beneficial when eatena day before or a day after bleeding; but on the third day it is to be avoided as dangerous. Milk, cheese, onions, and cress are dangerous after the operation, and he who is imprudent enough to partake of them must drink a mixture made of one-fourth of a log of wine and the same quantity of vinegar (Shab. 129a; Ned. 54a; 'Ab. Zarah 29a).
Nearly all of these rules emanate from Rab and Samuel, who were among the earliest and most prominent Babylonian amoraim (third century). But not all of them met with general approval. A century later it was said of them, "Now that many trample these precepts under foot, and yet escape serious hurt, one can realize the truth of the psalmist's saying (Ps. cxvi. 6), 'The Lord preserveth the simple'" (Shab. 129b; Yeb. 72a). See Brecher, "Das Transcendentale im Talmud," § 57, and Abba the Surgeon (Umana).