Rabbi Yonasan Steiff was dayan of Budapest and, in America, rav and rosh yeshiva of the Viener Kehillah. In his introductory lecture to talmidim, he exhorted them to learn Torah, because knowledge of Torah is one's insurance against getting swept up into the heretical movements of the time:
In Hallel we say: House of Israel, trust in Hashem; He is their help and shield (Tehillim 115:9). The word He is added to show that only He can help us, and only to Him do we look for our salvation. This idea is repeated in the following two verses: House of Aharon, trust in Hashem; He is their help and shield. Those who fear Hashem, trust in Hashem; He is their help and shield.
The Oral Tradition teaches that the Omer Sacrifice was always harvested on the night following the first day of Pesach, and offered in the Beis Hamikdash on the second day of Pesach. The Mishnah in Menachos (65a) says that the heretical Baithusian sect disputed this tradition of Chazal, and held that the Omer should be harvested on the first Saturday night and offered on the first Sunday after the first day of Pesach. To combat the influence of this sect, Chazal enacted that the Omer be harvested with great fanfare, before a large crowd of people. The man designated to cut it would say to the crowd, “Has the sun set?” They would say, “Yes!” “Has the sun set?” “Yes!” “Has the sun set?” “Yes!” Then he would ask, “With this sickle!” They would say “Yes!” And so on three times. “With this basket?” “Yes!” “Should I cut?” “Cut!” Each question and answer was repeated three times, in order to reinforce the true interpretation of the Torah handed down to us by Chazal.
And the wise Rabbi Samson Raphael Hirsch in his Siddur writes that Chazal took a similar approach to the prohibition to fight wars during exile. They composed the fourth blessing of Birkas Hamazon: "He did good, He does good, He will do good to us; He bestowed upon us, He bestows upon us, He will bestow good upon us forever." They wished to instill faith in Jewish hearts, so that they should never again trust in false messiahs or attempt to help themselves, but rather to trust in G-d's great name alone, that He would certainly fulfill His promise: "If your exiles will be on the edge of heaven, from there Hashem your G-d will gather you and take you" (Devarim 30:4).
All of the above is found in Shas and Poskim, such that for whoever learns Shas, all these things are obvious, and there is no need even to bother writing them. It is well known that such was the ancient Jewish belief passed down to us by the Tannaim and Amoraim, who in turn received it from the generations before them, all the way back to Moshe Rabbeinu. Therefore, nowadays anyone who wants to escape the influence of all the crooked and empty movements must study the Oral Torah, and then he can be sure of his path, for the Oral Torah is the strong bridge leading to truth and justice. (Rabbi Yonasan Shteif, Introduction to Chadashim Gam Yeshanim on Chullin, p. 33)