Living Persons and Organ Donation
Sometimes there is a conflict between the mandate to save lives and the mandate to avoid health risks.
A number of ethical quandaries regarding organ donation arise from both living‑related and cadaver organ donation. The issues pertaining to living‑related organ donation primarily involve risk to the donor. In Judaism, it is forbidden to sacrifice one's life in order to save another:
["Your life comes before that of another" (Babylonian Talmud, Bava Metzia 62a)]
and to deliberately endanger oneself
["Take heed of yourself, and take care of your life" (Deuteronomy 4:9).
Other sources are:
"Take good care of your lives" (Deuteronomy 4:15), and
"A man should not place himself in danger" (BT, Shabbat 32a)].
However, not all risks are equivalent. Certain risks are an inherent part of life
["The multitude has trodden upon them" (BT, Shabbat 129b)].
Yet, in Judaism, people are considered to be responsible for one another
["All of Israel is responsible one for the other" (BT, Shevuot 39a)]
and are legally held to such a standard
["Whence do we know that if a man sees his neighbor drowning or mauled by beasts or attacked by robbers, that he is bound to save him? From the verse 'Neither shall you stand idly by the blood of thy fellow'" (BT, Sanhedrin 73a).
"Whoever is able to save another and does not save him transgresses the negative commandment, 'Neither shall you stand idly by the blood of thy fellow'" (Maimonides, Mishneh Torah, Hilchot Rotzeach 1:14)].
Thus, the issue becomes one of degree. How much risk is one required to assume in order to "save the life of another" without "stand[ing] idly by the blood of one's brother" (Leviticus 19:16)?
The rabbis have taught that while it is not obligatory to risk one's life to save another, it may be praiseworthy to do so under certain circumstances. The Radbaz (Rabbi David ben Zimra, 16th century) refers to such an individual as hasid shoteh (pious fool). According to the Aruch HaShulchan, Choshen Mishpat 426:4, "...[it] depends on the circumstances. One must weigh the matter on a scale, and not safeguard himself more than necessary."
Therefore, the permissibility for one to donate an organ is dependent on the risk of the particular procedure in question. For example, donating blood is permitted, if not mandated, because the dangers and pain involved are minimal (M. Feinstein, Igrot Moshe, Choshen Mishpat #103). Donation of bone marrow is slightly more hazardous, but only minimally so; however, it is associated with considerably more discomfort. Thus, donating bone marrow is permitted, and some authorities might even consider it to be obligatory.