The author, R. Joseph David Moskowitz (1910-1970) was the Rebbe of Sasov and Shotz. He was the son of R. Yitzchak Moskowitz of Shatz-Sassov (1877-1958), and became known as the Shotzer Rebbe of New York when his father died. He never married and therefore left no children to replace him as rebbe. He wrote that one his goals in writing the book was to encourage the study of the laws of the Sabbath and eruvin. He states in his introduction that it is not his intention to give a psak, a halakhic decision, on the matter. Approbations from R. Yosef Eliyahu Henkin, R. Moshe Feinstein, R. Yonatan Steif and a letter from R. Menachem Schneersohn are included. This book also contains a chronological list of all the eruv activities in the US from the late 19th century onwards (p. 164-170). In addition, R. Moskowitz included his late father's will and other related material (pp. 157-160).

An eruv is a religious boundary that is erected around Jewish communites throughout the world. An eruv usually consists of a series of poles connected by galvanized steel wire that circumscribe the Jewish community. They often incorporate existing municipal infrastructure such as utility poles and electrical wires, so long as they are used in accordance with the lengthy and complex set of kosher architectural laws set forth in the Talmud.

The construction of eruvin stems from the observation of the Sabbath, the weekly sacred day of rest (Friday sundown to Saturday sundown) that includes a prohibition against carrying objects outside of one's home, or private domain. The actual Biblical declaration of this law states briefly but very specifically that the transferral of objects between public and private domains is a form of work and hence a violation of the Sabbath. The reason Jews construct eruvin is that according to most Rabbinic authorities, the shared public space within an eruv is considered the private domain of the community. In this way, observant Jews can carry their keys or prayer books on the Sabbath while acting in accordance with sacred principles.

בעמ' האחרון: ציור העיר <אי> מאנהעטען, מעשי ידי ר' יוסף ב"ר ישראל המכונה קעזדין. הסכמות: ר' יוסף אלי' ב"ר אליעזר הענקין, יב כסלו תשי"ט; ר' משה פיינשטיין, כח ניסן תשי"ט; ר' יונתן שטייף, ו קרח תשי"ד; ר' מ[נחם] שניאורסאהן, ברוקלין, ד ניסן תשי"ט.