cannot be harmed by damaging forces.
The Agrah D’Pirkah adds that this is also seen from the verse in Tehillim (37:3): “Trust in Hashem and do good.” This indicates that trusting in Hashem alone was not enough for Dovid Hamelech, as even wicked men can rely on bitachon. Rather, he also wanted to do good.
Rav Dovid Yitzchok of Skolya zy”a asks how one can have bitachon that Hashem will help him if he knows that he is undeserving. He answers that one who trusts in Hashem merits seeing open supernatural miracles, even though he will be punished separately for his sins.
Before Turning to Doctors, Turn to Hashem:
The pasuk states (Shemos 21:19): “He shall only give him his wages for missed work and pay the costs for the doctor to heal him.” Chazal (Brachos 60A) learn from this pasuk that a doctor has permission to heal the sick.
Sefer M’Zekeinim Esbonen quotes Rav Mordechai Chaim of Slonim zy”a as citing the verse (Yeshaya 44:6): “I am first and I am last, and besides for Me, there is no G-d”, and explaining in the name of Rav Dovid Lubliner zy”a (a resident of Tzefas and student of Rav Shmuel of Kaminka zy”a and the Ruzhiner Rebbe zy”a) that when most people get sick, they first go to a doctor and, if that doesn’t work, they daven to Hashem. The pasuk is saying that this should not be the case. Hashem should be first and last, and the doctor should only be secondary.