Ezra 2:62

Priesthood. Those who cannot prove that they are priests, ought not to exercise the functions. (Worthington) --- The Jews were particularly careful to preserve their genealogical tables, and transcribed them again after any very troublesome times. (Josephus, contra Apion 1, and in his own Life.) --- The Rabbins falsely assert that only the mother's side was examined, and that the children followed her condition. (Calmet)