Nathan ben Meshullam was asked to give a reason for the duration of the present exile, while that of Babylon, which was inflicted upon the Jews as a punishment for the worst of crimes, idolatry, lasted only seventy years.
Nathan ben Meshullam was summoned to provide an explanation for the duration of the present displacement, in contrast to the relatively brief exile of Babylon, which was imposed on the Jews due to their grave sin of idolatry.