Born in Praga (near Warsaw). After serving as a cantor in Poland and Germany, he moved to London, and worked there as a cantor until his death. Among his compositions are oratorios, cantatas and hymns. The catalogue of the National Library of Israel includes twenty-four items by Hast. One of the rare items is Hast's earliest collection of synagogue music from 1878 which he edited in collaboration with the Polish Jewish composer Michal (Michel) Bergson (1820-1898), father of the renowned philosopher Henry Bergson.
The Jewish Encyclopedia offers a review of Hast's life while he was still alive based on contemporary resources. The entry was written by the Reverend Francis L. Cohen.
A detailed biographical note about Hast by Aron Friedmann appeared in the Allgemeine Zeitung des Judenthums 82, no, 29 (19.7.1918), pp. 341-3. This is the most substantial source on Hast in any language
The four volumes of Hast's Avodat Haqoddesh are downloadable here.
A (slightly edited and amended) note by Daniel Tunkel (May 2010) in response to a query regarding Hast that appeared in the yahoo group jewishulmusic:
Hast claims to have published the first volume of Ashkenazi Synagogue music in
Hast served as the chief cantor of the Great Synagogue, Duke's Place,
There is a nice portrait of Hast in middle age in the section on the Great Synagogue in Peter Renton's book The Lost Synagogues of London (Tymsder Books).