GEN222 A doctor is obligated to heal the sick to the best of his abilities.
Shulchan Aruch, Yoreh Deah 336:1 One may ask, “Since healing is in the hands of Hashem, why does the doctor have an obligation to heal?” Hashem created a world of “cause and effect” directed by Him alone. [this verse] This reality gives a human being the most basic aspect of his humanity: free will. Because a person eats, he feels satiated; therefore, he can choose to do the mitzvah of feeding the hungry. Because he has money he can buy food and clothing; therefore, he can choose to give tzedakah to the poor and alleviate their plight. A disease is cured by a certain medication; therefore, a doctor can prescribe it and perform the mitzvah of healing the sick. This is the purpose of creation: to choose that which is right and to avoid wrong.
Deuteronomy 30:15 Thus, the world of “cause and effect” is the framework within which a person can operate his “free will.” If a person wrongly exercise free will by recklessly exposing himself to disease or danger, he violates the basic injunction to guard his life and health which were Divinely bestowed to accomplish his life’s tasks. He then deserves the effect of illness or accident that he chose to bring upon himself.
Talmud, Ketubos 30a However, Hashem may decide to bring illness even on a person who acted very responsibly, and directs the cause and effect toward that end. If Hashem wants a person to be fed, He will cause him to meet his kindly benefactor Similarly, if Hashem wants an ill person to recover, He will cause him to meet the doctor who will heal him However, if Hashem does not wish the person to be healed, He will direct “cause and effect” that way. Thus, Hashem alone directs “cause and effect.” Our task in life is to exercise free will. A doctor can choose to treat a patient, exercising his free will for “right”; he has chosen to fulfill Hashem’s mitzvah of returning a person to life and health.
Yoreh Deah ibid. If he chooses “wrong,” and does not treat the patient, his negligence is considered tantamount to murder.
Talmud, Nedarim 40a JOURNEY 520-1
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