||R. Abraham b. Jehiel Michal Danzig (Danziger) (1748–1820), was born in Danzig, he studied in Prague at the yeshivot of R. Joseph Liebermann and R. Ezekiel Landau. True to his family tradition, he refused to derive any material gain from his studies and earned his livelihood as a merchant. Although required at times to travel long distances to trade fairs in Germany, he continued to learn with great devotion. From 1794 to 1812 he served as dayyan in Vilna, in an honorary capacity; only in his old age, after losing his possessions, was he obliged to accept remuneration for his services. Danzig wrote a number of halakhic works, but his fame rests upon two publications: Hayyei Adam ("Man's Life"), covering all the laws of the Shulhan Arukh dealing with daily conduct, based on the Orah Hayyim sections, with an addendum called Nishmat Adam, in which he justified his decisions which were not in accordance with the accepted view (Vilna, 1810); and
Hokhmat Adam ("Man's Wisdom") covering all the laws of the Shulhan Arukh dealing with the dietary regulations etc. contained in the Yoreh De'ah section, with an addendum called Binat Adam, which included discussions on various relevant halakhic subjects and responsa (Vilna, 1812).
Both works were initially intended for youthful students and for educated laymen not fully versed in rabbinic literature who, in attempting to determine Jewish law, found themselves unable to grapple with the intricacies of the Shulhan Arukh and with its maze of conflicting opinions. In these works, Danzig shows himself possessed of considerable pedagogical talent. He arranges the laws methodically, defines his terms lucidly and precisely, presents the various views and their sources, and renders his own decisions and his reasons for them - all in clear, simple language. The pleasant tenor of his writing, which is suffused with unquestioning faith and true piety, contributed largely toward the acceptance of his works.
Hayyei Adam appeared in almost a hundred editions. Groups called "Hevrot Hayyei Adam" were formed in several communities for the regular study of the code. Danzig's merits as a codifier were recognized also by renowned rabbis and codifiers, who gave due consideration to his decisions. His books include much of historical interest with regard to the daily life of Lithuanian Jewry in his generation.