Halakhah do Liczb 5:11

LAWS CONCERNING A WOMAN SUSPECTED (BY HER HUSBAND) OF INFIDELITY.
These comprise three precepts, of which one is an affirmative precept, while two are negative precepts. They are, in detail, as follows: 1) to do unto the woman suspected of infidelity according to "the law of jealousy" set forth in the Torah (Num. 5:11-31); 2) not to put oil on her offering; 3) not to put frankincense on it.

Rav Shlomo Zalman (Teshuvot Minchat Shlomo 1:91:24) maintains that we withhold these extreme life-saving measures if so requested by the gosseis. He adds that although this is permissible, it is preferable to explain to the patient that Torah philosophy advocates living as long as possible even if one experiences pain, as is indicated by the Mishnah in the context of a sotah³The Torah states that a sotah (woman suspected of adultery, see Bemidbar 5:11-31) who is found guilty will die a hideous death. However, if she has “merit,” Hashem will grant her a few extra years of life, during which she will slowly deteriorate and experience difficult illness. This indicates that it is preferable to die a slow and painful death rather than die immediately, as the Mishnah teaches that the extra years of life involving great suffering result from merit. (Sotah 3:4; also see Rambam Hilchot Sotah 3:20) and the Mishnah (Avot 4:22) that states, “One hour of teshuvah and good deeds in this world is better than all of the world to come.”⁴See, however, Ketubot 33b, Sotah 46b, Rashi’s comments to Shemot 15:5 s.v. Kemo Even, Teshuvot Igrot Moshe Y.D. 2:174:3, and Rav Hershel Schachter’s B’ikvei Hatzon 34 for situations in which it seems it is preferable to die immediately rather than suffer a prolonged, painful death.