source: https://www.myjewishlearning.com/article/euthanasia-medieval-sources/
The major codes of Jewish law forbid actions that hasten death, but some allow the removal of impediments to death.
The twelfth‑century code of Maimonides treats our subject matter [of euthanasia] as follows:
“One who is in a dying condition is regarded as a living person in all respects. It is not permitted to bind his jaws, to stop up the organs of the lower extremities, or to place metallic or cooling vessels upon his navel in order to prevent swelling. He is not to be rubbed or washed, nor is sand or salt to be put upon him until he expires. He who touches him is guilty of shedding blood. To what may he be compared? To a flickering flame, which is extinguished as soon as one touches it. Whoever closes the eyes of the dying while the soul is about to depart is shedding blood. One should wait a while; perhaps he is only in a swoon.”