Alternatively, perhaps the user is mistaken, and they meant another text or a different chapter number. Alternatively, maybe they are referring to a book named "Tanya" that isn't the Alter Rebbe's Tanya. Let me check if there is another text called Tanya. There are other works by the Chassidic masters, like the Tanya of Tzemach Tzedek, but those are part of the same tradition and still part of the Tanya corpus.
Alternatively, perhaps the user is referring to the Talmud. The Talmud has tractates with more than 150 chapters. For example, Tractate Berachot has 9 chapters, Ketubot has 9 chapters, etc. But again, 157 is too high for any single tractate. tanya 157
Alternatively, the user could have confused the numbering with another edition. For example, some reprints might number the same content differently, but generally, the structure remains consistent. The 59 chapters are standard. Alternatively, perhaps the user is mistaken, and they