The most famous issue concerning trust in God is when does one do "effort" [Hishtadlut]? This is an argument among rishonim [first authorities. i.e. authors from the Middle Ages] And it is a known fact that concerning any argument among rishonim each is "the words of the Living God" so you do not expect to find a resolution. [note 1] [The way this is referred to in Hebrew is "a machloket Rishonim" "argument of first authorities". Once you have gotten to the point something is a Machloket Rishonim that is the resolution of the discussion.]   For example if you find an argument between the Ri and Rabbainu Tam you do not expect to find a complete solution. You rather expect to find support for one or the other. You never expect to disprove one or the other. If one thinks he has disproved a Rishon that means he is either stupid or insane. [note 2]
  [It would be like today if someone says they can accurately predicate the value of  a stock or the whole stock market in the ten ten years. They simply means the fellow thinks he is a lot smarter than he really is.] [I do not know the reason for this. It probably has to do with a fact noted by Michael Huemer that the logic of the Middle Ages was always logically rigorous. The problems had to do with the beginning axioms. After the Middle Ages the axioms always sound a lot better but the logic is almost always circular. Notes: [note 1] The idea of "these and these are the words of the living God" comes from the Gemara in terms of arguments among the sages of the Gemara or Mishna. The idea is that even if it has been decided that the law is like or or the other, that does not mean the other was wrong. Rather "both are the words of the living God" even though the law was decided by one.] [note 2] This does not apply to "achronim" people that wrote after the Beit Yoseph [Rav Yoseph Karo].[After the Middle Ages] They can be wrong and often are. [note 3] Reb Israel Salanter published a monthly magazine "tvuna". In it, he mentions that the opinion of the Ramban is to have trust with no effort. I think this was a mistake of the printer. Rather, he actually was refering to the opinion of the Rambam . [The Rambam and the Chovot Levavot both hold with this approach for people that devote themselves to sitting and learning Torah and serving God all day. Thus, when the Madragat HaAdam [a disiple of Israel Salanter] writes about trust in god with no effort he quoted the Ramban--. He was drawn after that mistake of the printer. But he also quotes the Gra in Mislei (Proverbs) who in fact holds with this approach of trust with no effort. I might add here that the case of king Asa is sometimes brought up, and I have heard people say his mistake was to trust in the doctors alone. But, that is a mistake. The verse itself makes it clear that by going to the doctors, that in itself was not trusting in God, i.e., the verse makes it clear you can trust in God or in the doctors not both. It is a case of the exclusive ""or”. This or that, but not both.]------I myself think that doctors today are different because there have become procedures that are common. I think the case of King ASA was when medicine was less understood. i think there is a difference between parnasa [making a living] and medicine. So today I think going for generally accepted procedures is like parnsa. It is in experimental medicine [i.e., medicine that has been around for 50 years or less.] that there is a problem.-------------------ר' ישראל סלנטר published a monthly magazine "תבונה". In it, he mentions that the opinion of the רמב''ן is to have trust in God with no effort. I think this was a mistake of the printer. Rather, he actually was referring to the opinion of the רמב''ם. [The רמב''ם and the חובות לבבות both hold with this approach for people that devote themselves to sitting and learning Torah and serving God all day. Thus, when the מדרגת האדם [a disciple of ישראל סלנטר] writes about trust in God with no effort he quoted the Ramban--. He was drawn after that mistake of the printer. But he also quotes the גר''א in משלי who in fact holds with this approach of trust with no effort. I might add here that the case of king אסא is sometimes brought up, and I have heard people say his mistake was to trust in the doctors alone. But, that is a mistake. The verse itself makes it clear that by going to the doctors, that in itself was not trusting in God, i.e., the verse makes it clear you can trust in God or in the doctors not both. It is a case of the exclusive ""or”. This or that, but not both. I myself think that doctors today are different because there have become procedures that are common. I think the case of King אסא was when medicine was less understood. I think there is a difference between making a living(פרנסה) and medicine. So today I think going for generally accepted procedures is like פרנסה. It is in experimental medicine [i.e., medicine that has been around for 50 years or less.] that there is a problem.-----------------------ר' ישראל סלנטר פרסם מגזין חודשי "תבונה". בו הוא מזכיר שדעת הרמב"ן (משה בן נחמן) היא לבטוח בה' ללא השתדלות. אני חושב שזו הייתה טעות של המדפיס. אלא שהוא התייחס לדעת הרמב"ם. [הרמב"ם והחובות לבבות מחזיקים בגישה עבור אנשים שמקדישים את עצמם ללימוד תורה ועבודת ה' כל היום. לכן, כאשר המדרגת האדם כותב על בטחון בה' ללא מאמץ, הוא ציטט את הרמב"ן. הוא נמשך אחרי הטעות הזו של המדפיס. אבל הוא גם מצטט את הגר"א במשלי שלמעשה מחזיק בגישה זו של בטחון ללא מאמץ. אני חייב להוסיף כאן שמקרה של המלך אסא מועלה לפעמים, ושמעתי אנשים אומרים שהטעות שלו הייתה לבטוח ברופאים בלבד. אבל, זו טעות. הפסוק עצמו מבהיר שעל ידי פנייה לרופאים, זה כשלעצמו לא היה אמון באלוהים, כלומר, הפסוק מבהיר שאפשר לבטוח באלוהים או ברופאים, לא בשניהם. זהו מקרה של "או" בלעדי. זה או זה, אבל לא שניהם. אני עצמי חושב שרופאים כיום שונים משום שיש מהלכים שהפכו להליכים נפוצים. אני חושב שהמקרה של המלך אסא היה כשהרפואה הייתה פחות מובנת. אני חושב שיש הבדל בין פרנסה לרפואה. אז היום אני חושב שהליכים מקובלים הם כמו פרנסה. דווקא ברפואה הניסויית [כלומר, רפואה שקיימת 50 שנה או פחות] יש בעיה