[2] His parents intended for him to pursue a commercial career, and for a short time he was employed as a clerk by a local business.
The following two years he spent in Vienna, where he worked as an assistant teacher and librarian in the city's Jewish school.
Zirndorf later chronicled these reminiscences in Isaak Markus Jost und Seine Freunde (1886).
In 1884, Zirndorf assumed the position of a history professor at the Hebrew Union College in Cincinnati.
He was appointed rabbi and preacher of the Ahabath Achim congregation in Cincinnati in 1889, a position he held until his death.