דברי הימים א, פרק כ״ד, פסוק כ״א

Organizing the ancestral families required clear lines of authority and representation. The primary approach among commentators is that a specific division of leadership was established within the family of Rehabiah. Out of all his sons, a man named Isshiah was chosen to serve as the head and leader of the family. Following his appointment to this senior position, the entire ancestral house was named after him.