Bava Kamma 85a:
תניא דבי ר' ישמעאל אומר (שמות כא, יט) ורפא ירפא מכאן שניתן רשות לרופא לרפאות
It is taught in a Braisa: The academy of R’ Yishmael says: “Heal, he will heal” - from here [we learn] that permission is given to a doctor to heal.
Tosfos there:
וא"ת והא מרפא לחודיה שמעינן ליה וי"ל דה"א ה"מ מכה בידי אדם אבל חולי הבא בידי שמים כשמרפא נראה כסותר גזירת המלך קמ"ל דשרי:
If you ask: But from “heal” alone we would hear [that a doctor can heal - why do we need “heal, he will heal”]? There is to say: I might have thought that these words are by a wound caused by man, but for an ailment that comes from Heaven, when he heals, it appears like he’s contradicting the decree of the king; it comes to teach us that it is permitted.
There seems to be two problems with Tosfos’ logic:
1. Why isn’t healing a wound caused by man also an issue of “it appears like he’s contradicting the decree of the king”?
Contrast with Shabbos 32a:
תנא דבי רבי ישמעאל כי יפול הנופל ממנו ראוי זה ליפול מששת ימי בראשית שהרי לא נפל והכתוב קראו נופל אלא שמגלגלין זכות על ידי זכאי וחובה על ידי חייב
The academy of R’ Yishmael taught: “For the one who falls will fall from it” - this one is fitting to fall since the six days of creation. For he has not fallen, yet the passuk calls him “the one who falls.” Except that good things comes by one who is innocent and bad things come by one who is guilty. [Therefore, build a fence so that it doesn’t come by your hands - Rashi to Devarim 22:8.]
(Notice that this Gemara was also taught by the academy of R’ Yishmael!)
By the same logic that the one who would fall was destined to fall anyway, just don’t be the messenger by which it occurs, why can’t one say that this person was destined to be injured anyway, just one shouldn’t be the messenger? In other words: Even injuries caused by man are decrees of the king, and if one heals such a wound, it should be no different than if one heals an ordinary illness! Therefore, once we see that wounds caused by man aren’t an issue from ורפא alone, we don’t need an additional teaching that it’s permissible to heal ailments from Heaven, since it’s all the same thing anyway.
2. “It appears like he’s contradicting the decree of the king” isn’t a valid argument
Contrast further to Bava Basra 10a:
תניא היה רבי מאיר אומר יש לו לבעל הדין להשיבך ולומר לך אם אלהיכם אוהב עניים הוא מפני מה אינו מפרנסן אמור לו כדי שניצול אנו בהן מדינה של גיהנם וזו שאלה שאל טורנוסרופוס הרשע את ר"ע אם אלהיכם אוהב עניים הוא מפני מה אינו מפרנסם אמר לו כדי שניצול אנו בהן מדינה של גיהנם
It was taught in a Braisa: R’ Meir used to say: There is for an opponent to argue to you and say to you: “If Hashem your G-d loves the poor, why doesn’t He sustain them?” Say to him: “So that we may be saved through them from the judgement of Gehennom.” This is the question that the wicked Turnus Rufus asked R’ Akiva, “If Hashem your G-d loves the poor, why doesn’t He sustain them?” [R’ Akiva] said to [Turnus Rufus], “So that we may be saved through them from the judgement of Gehennom.”
אמר לו [אדרבה] זו שמחייבתן לגיהנם אמשול לך משל למה הדבר דומה למלך בשר ודם שכעס על עבדו וחבשו בבית האסורין וצוה עליו שלא להאכילו ושלא להשקותו והלך אדם אחד והאכילו והשקהו כששמע המלך לא כועס עליו ואתם קרוין עבדים שנאמר (ויקרא כה, נה) כי לי בני ישראל עבדים
[Turnus Rufus] said to [R’ Akiva], “To the contrary, that’s what obligates you to the judgement of Gehennom! Let me pose to you a parable. To what is this comparable? To a human king who became angry at his servant, imprisoned him, and commanded that nobody give him to eat or drink. A man went and gave him to eat and drink. When the king hears, should he not be angry at him? And you are called servants, as it says, ‘For to me are the Jews as servants’!”
אמר לו ר"ע אמשול לך משל למה הדבר דומה למלך בשר ודם שכעס על בנו וחבשו בבית האסורין וצוה עליו שלא להאכילו ושלא להשקותו והלך אדם אחד והאכילו והשקהו כששמע המלך לא דורון משגר לו ואנן קרוין בנים דכתיב (דברים יד, א) בנים אתם לה' אלהיכם
R’ Akiva said to [Turnus Rufus], “Let me pose to you a parable. To what is this comparable? To a human king who became angry at his son, imprisoned him, and commanded that nobody give him to eat or drink. A man went and gave him to eat and drink. When the king hears, should he not send him gifts? And we are called sons, as it says, ‘You are sons to Hashem your G-d’!”
אמר לו אתם קרוים בנים וקרוין עבדים בזמן שאתם עושין רצונו של מקום אתם קרוין בנים ובזמן שאין אתם עושין רצונו של מקום אתם קרוין עבדים ועכשיו אין אתם עושין רצונו של מקום אמר לו הרי הוא אומר (ישעיהו נח, ז) הלא פרוס לרעב לחמך ועניים מרודים תביא בית אימתי עניים מרודים תביא בית האידנא וקאמר הלא פרוס לרעב לחמך:
[Turnus Rufus] said to [R’ Akiva], “You’re called sons and servants. When you do the will of Hashem, you are called sons. When you don’t do the will of Hashem, you’re called servants. And now you are not doing the will of Hashem!” [R’ Akiva] said to [Turnus Rufus], “Behold, it says, ‘Is it not to break bread for the hungry and bring the poor that are cast out into your house?’ When do we bring the poor that are cast out into the house? Now [that the Roman soldiers are occupying them]! And it says, ‘Is it not to break bread for the hungry?’”
Why should healing be any different than giving Tzedakah? The same way that Hashem gives poverty in order to provide merit for others on the poor’s behalf, so too, we should argue that Hashem gives ailments in order to provide merit for others on the sick’s behalf. The same way that we bring them in to help them monetarily, we should bring them in to help them medically. (Sanhedrin 73a provides precedent for such a comparison, deriving that one is obligated to save someone’s life a fortiori from the obligation to save someone’s property.)
TLDR
If Tosfos are not providing a valid line of logic, then, well, it’s not a valid line of logic. And if they are providing a valid line of logic, then why does it only apply to ailments by Heaven and not to wounds by man? As such, their original question - why are both terms “Heal, he will heal” necessary - returns. How can Tosfos be defended?
