Filaret's zeal for the purity of Orthodoxy sometimes led him into excesses but he encouraged the publication of theological works, formed the nucleus of the subsequently famous Patriarchal Library, and commanded that every archbishop should establish a seminary for the clergy, himself setting the example. Another great service rendered by Filaret to his country was the reorganization of the Muscovite army with the help of foreign officers. His death in October 1633 put an end to the Russo-Polish War (1632–33), withdrawing the strongest prop from a tsar feeble enough even when supported by all the weight of his authority.