On Donating Organs

An excerpt from a letter dated April 14, 1969:

...With regard to the question of leaving one's eyes to an eye-bank after 120 years, or similar bequests, I am of course reluctant to discuss this subject, since this whole matter is of no immediate concern to you at all, inasmuch as you have many many years to live and to fill them with productive and joyful activities, etc. However, since you have already raised this question, and in view of the fact that there are various misconceptions about it which have gained currency, I cannot pass over this question without telling you that there is a clear and distinct Psak-Din [halachic ruling], which leaves no doubt as to what the position of our holy Torah and religion is in regard to this matter. It is that not only is the Neshama [soul] – חלק אלו-ה ממעל ממש – "Verily a part of G‑dliness Above" in the words of the Tanya, but also the body of a Jew is sacred and is the property of G‑d, while the Jew is no more than a guardian of it.

This position explains also many Dinim (rules) relating to the body, having to do with hygiene and the like, which are also part of our Torah. Thus the Halacha rules explicitly that one must not mutilate, G‑d forbid, something which belongs to G‑d, and which has been placed in the care of a person as guardian and keeper. For the same reason, our Sages of blessed memory have been so strict in the matter of mutilating dead bodies. In those exceptional cases, which are very rare, where an exception was made to the rule, it is because of special reasons, which in no way diminished the sanctity and inviolability of the body, as G‑d's property, but only because under special circumstances, G‑d Himself has permitted certain isolated exceptions, in which case it is the Owner's will that is being carried out, namely G‑d's will...