Our Gemara on amud beis provides principles for deriving halachic rulings from precedent and observed behaviors of authoritative sources and rabbis:
One may derive the halakha neither from a statement nor from an incident where one saw a ruling issued in a certain manner, unless the Sages explicitly tell him that it is the practical halacha. If he asked the Sages and they told him the practical halakha, he may go and act upon the ruling in those circumstances…
Rashbam (ibid) elaborates that two situations fulfill the criterion of relying on a sage for practical halacha. Either when a theoretical teaching is studied and the rabbi affirms that a particular opinion may be relied upon in actual practice, or when a real-life question is asked and ruled upon contemporaneously with full permission to act in accordance with the decision.
In Devarim (17:8–11), the Torah instructs:
If a case is too baffling for you to decide, be it a controversy over homicide, civil law, or assault—matters of dispute in your courts—you shall promptly travel to the place that Hashem, your God, will have chosen, and appear before the Levitical priests, or the magistrate in charge at the time, and present your problem. When they have announced to you the verdict in the case, you shall carry out the verdict that is announced to you from that place that Hashem chose, observing scrupulously all their instructions to you. You shall act in accordance with the instructions taught to you that you shall do, and you must not deviate from the verdict that they announce to you either to the right or to the left.
The Sefer Daf Al Daf quotes the Sefer Beis Yitzchok (Shoftim), which notes the seemingly excessive verbosity in these verses. It says (1) you shall carry out the verdict that is announced to you; (2) following scrupulously all the Torah taught to you; (3) you shall act in accordance with the instructions taught to you that you shall do; and (4) you must not deviate from the verdict that they announce to you either to the right or to the left.
Clauses one and four are understandable, as they emphasize the importance of initially seeking instruction and then accepting the authority of the ruling. However, clauses two and three seem redundant. The Beis Yitzchok explains (quoting his son), in light of our Gemara, that these clauses correspond to the two precedents discussed by Rashbam. Clause two—following scrupulously all the Torah taught to you—refers to theoretical teachings affirmed by a rabbi for practical application, while clause three—you shall act in accordance with the instructions taught to you that you shall do—refers to the practical ruling on an actual situation.
While discussing this famous selection from the Torah, it’s important to address a common misapplication of this verse that has led to a form of religious bullying. The verse (ibid 11) seems to instruct blind faith, which is sometimes used to tell anyone without the status of a venerated sage that their very act of disagreement is heretical. After all, the verse states: “You shall act in accordance with the instructions given to you and the ruling handed down to you; you must not deviate from the verdict that they announce to you either to the right or to the left.”
On this verse, Rashi famously quotes the Sifri:
Even if [the judge] tells you that what appears to you to be right is left, or that what appears to you to be left is right, you must obey him; how much more so if he tells you that what is right is right and what is left is left.
This is sometimes used to intimidate people into denying their own common sense: “You see, one must even believe that their right hand is their left if their rabbi says so.”
However, this is a misinterpretation. This verse and derasha refer to the Sanhedrin, not to a local orthodox rav or even possibly a local rosh yeshiva. There is an argument that it may extend to the Godol Hador, as he may function in place of the Sanhedrin. But even if this is the case, the Sanhedrin itself was only empowered to compel the rebellious elder to refrain from publicly preaching his halachic opinion if they contradicted the ruling of the Sanhedrin, not his peshatim or ideas, (see Rambam, Mamrim chapter 3). The obligation to follow the Sanhedrin was a legal necessity to avoid anarchy, as stated in Sanhedrin (88b): “so that discord would not proliferate in Israel.” This does not imply that disagreement, when done in good faith, is heresy. While in heated controversies, such as those between religious Zionists and anti-Zionists or between Chassidim and Misnagdim, accusations of heresy may have flown, it is hard to argue that either side’s position, however misguided, was truly heretical.
Chovos HaLevavos offers an even more fascinating idea. In his introduction, he points out that the verses we quoted about bringing difficult cases to the Sanhedrin all refer to monetary, halachic, and legal matters. They do not refer to questions of faith, or to how one should pray, or how to overcome jealousy or anger in one’s heart. Why not? Shouldn’t these matters be of utmost importance to clarify before the highest authority? Chovos HaLevavos answers that when it comes to matters of the heart, you are responsible to delve inward and find the answers yourself. Of course, this doesn’t mean, “Don’t ask rabbis for guidance.” We must all be humble and learn Torah and hashkafa from great people and talmidei chachamim. Chovos HaLevavos says that you should reflect on such matters in your heart and apply your intellect after first accepting them from Tradition. Still, he emphasizes that each person has an intellectual responsibility, as well as the right, to determine inner truths.