The Shulchan Aruch Harav: Background

The Shulchan Aruch Harav: Background of why it was written and why we follow his rulings
 
Historical background:[1]
The Shulchan Aruch Harav, also known as the Alter Rebbe’s Shulchan Aruch, or Shulchan Aruch Admur Hazakein; was written by Rav Schneur Zalman of Liadi.
Its initiation: The Maggid of Mezritch was encouraged by the heavenly courts to search amongst his students for a proper candidate to compile a new Shulchan Aruch.[2] The Maggid of Mezritch chose the Alter Rebbe to write this compilation.[3]
When was it written: It was written anywhere between the years 1765-1775.[4] Some[5] prove that the section of Orach Chaim was written in the years 1771-1772. The Rebbe Rayatz writes[6] that the Maggid asked Admur to write the Shulchan Aruch when he was 21 years old.[7] The other sections of the Shulchan Aruch were written at a later time. An exact date has not been historically proven.[8]
How long did it take to write?[9] The section of Orach Chaim was written by Admur in a span of two years.
When was it printed? The Shulchan Aruch was first printed in its entirety after the Alter Rebbe passed away, in the year 1816.[10] Certain sections of the Shulchan Aruch were printed beforehand. Hilchos Talmud Torah was printed in Shklov in the year 1794.[11]
The name “Shulchan Aruch Harav”: The source for this name “Shulchan Aruch Harav” is seemingly based on the title of “Rav” that was given to Admur by the students of the Maggid and the Maggid himself. The following is the story related to the giving of this title:[12] The Maggid once told Reb Zusha “write to our Gaon Reb Zalmana Litvak to come here”. Upon the students hearing that the Maggid referred to the Alter Rebbe as our Gaon, they gave him the  title “Rav”. When Reb Avraham Hamalach told this over to his father the Maggid, the Maggid replied “The Chevraya Kadisha have projected the truth in this statement. A name has meaning and the Halacha is like Rav. The Shulchan Aruch of the Rav will be accepted within all of Jewry.”
 
The purpose of its compilation and its necessity over the Shulchan Aruch of the Michaber:
The compilation of the new Shulchan Aruch was to serve a dual purpose:

1. To arbitrate between the many Halachic opinions that developed since the printing of the Shulchan Aruch of the Michaber.[13]
2. To explain the reasons behind the Halachas, hence lending the learner the ability to compare the reason to similar cases and hence come to a proper Rabbinical decision.[14]

 
The burning of the manuscripts:[15]
In the year 1810 the original manuscripts of the entire Alter Rebbe’s Shulchan Aruch were destroyed in a fire that broke out in Liadi.[16] The Alter Rebbe cried bitterly over this loss, and did not imagine he would get such Divine retribution. It is for this reason that many chapters, and selected laws within chapters, are missing from the available print, as the Shulchan Aruch was never formally printed until after the Alter Rebbe passed away, and by that time only copies, of parts of the original, remained.
 
Following the rulings of Shulchan Aruch Harav:[17]
Chabad Chassidim have accepted the rulings of the Shulchan Aruch Harav for all matters, whether for leniency or stringency. This applies even if majority of codifiers argue on his opinion. This is similar to those who follow the opinion of the Rambam [or Michaber] and do not divert from his opinion. The Maggid stated that the four cubits of Halacha are dependent on the Alter Rebbe and that even the first thought of the Alter Rebbe in a given topic is a glimmer of Divine spirit [Ruach Hakodesh].[18] His rulings and arbitrations are considered as if they were given on Sinai.[19] The Tzaddik, Reb Levi Yitzchak of Berditchiv writes[20] as follows: I testify heaven and earth that if the Alter Rebbe were alive in the times of the Rif and Rambam he would be considered like one of their contemporaries etc. His “words of gold” is literally like the words of the Rif and Rambam of blessed memory.”