Of Hus's Latin works, as already mentioned, the treatise De Ecclesia requires particular notice. The work, written when Hus was exiled from Prague, and probably finished in the year 1413, is to a great extent a transcript of Wycliffe's work on the same subject, and has therefore little literary interest. But neither the events of the life of Hus nor the ideas expounded in his Bohemian works are intelligible without some knowledge of the treatise De Ecclesia. The Roman Catholic hierarchy, far more powerful and far less dependent on public opinion in the fifteenth century than in the present day, could not but see that—independently of all dogmatic differences of opinion—the acceptation of views such as those contained in the treatise De Ecclesia must necessarily produce a fundamental change in the organisation of the Church.

The keynote of the treatise De Ecclesia[46] is Hus's peculiar doctrine with regard to predestination. He divides all men into two classes, those who are—either conditionally or unconditionally—predestined (predestinati) to eternal bliss, and those who are "foreknown" (presciti) to damnation. The mass of the predestinati form the true Holy Catholic Church,[47] but the Church as at present constituted includes the presciti as well as the predestinati. Of the true Church, Christ is the only Head. As man He is "Head of the Church within it" (caput intrinsecum), as God He is "its Head without it" (caput extrinsecum). Christ is the true Roman Pontiff, the High Priest, and the Bishop of Souls. The Apostles did not call themselves "Holy Father" or "Head of the Church," but servant of God and servant of the Church. A change came with the "donation of Constantine" (that singular fiction which played so large a part in the theological controversies of the Middle Ages). Since that time the Pope has considered himself as head (capitaneus) of the Church and Christ's vicar upon earth. It is, however, according to Hus, not certain that the Pope is Christ's successor in this world. He is then only Christ's representative and the successor of St. Peter, and the cardinals are only then the successors of the Apostles when they follow the examples of faith, modesty, and love which the former gave. Many Popes and cardinals have not done this, and, indeed, many saintly men who never were Popes were truer successors of the Apostles than, for instance, the present Pope (John XXIII.). St. Augustine did more for the welfare of the Church than many Popes, and studied its doctrines more profoundly than any cardinal from the first to the last. If Pope and cardinals give their attention to worldly affairs, if they scandalise the faithful by their ambition and avarice, then they are successors not of Christ, not of Peter, not of the Apostles, but of Satan, of Antichrist, of Judas Iscariot. Returning to his former point, it is not certain, Hus continues, that the Pope is really the head of the Church; he cannot even be sure that he is not prescitus; and therefore no member of the true Church at all. St. Peter erred even after he had been called by Christ. Pope Leo was a heretic, and Pope Gregory was but recently condemned by the Council of Pisa. It is a popular fallacy to imagine that a Pope is necessary to rule the Church. We must be thankful to God that He gave us His only Son to rule over the Church, and He would be able to direct it even if there were no temporal Pope, or if a woman occupied the papal throne.[48] As with the Pope and the cardinals, so with the prelates and the clergy generally. There is a double clergy, that of Christ and that of Antichrist. The former live according to the law of God, the latter seek only worldly advantage. Not every priest is a saint, but every saint is a priest. Faithful Christians are therefore great in the Church of God, but worldly prelates are among its lowest members, and may indeed, should they be presciti, not be members of the Church at all.

The Latin letters of Hus will be mentioned later in connection with those written in Bohemian.

Of greater literary interest than the Latin works of Hus are those written in his own language. The latter are written in a more independent and popular manner, and it is on them that his value as a writer depends. That Hus was a strong Bohemian patriot is, I hope, evident even from this short sketch of his life. Almost his first sermon referred to the oppression of his countrymen by the Germans, and no one more energetically aided the Bohemians in their endeavours to secure the control over the national university. Yet Hus was by no means a national fanatic or a hater of Germans, as has been so often stated. It is sufficient to refer to his often-quoted words: "If I knew a foreigner of any country who loved God more and strove for the good more than my own brother, I would love him more than my brother. Therefore good English priests are dearer to me than faint-hearted Bohemian ones, and a good German is dearer to me than a bad brother."[49]

Hus, like all Bohemian patriots, entertained a warm affection for the national language. One of his earliest writings deals with the correct spelling of the Bohemian language, and the diacritical signs still used in Bohemian are mainly an invention of Hus. He was also strongly opposed to the introduction of foreign words into the language, and refers to this subject frequently in his "Exposition of the Ten Commandments." In that work he sharply attacks the citizens of Prague who interspersed their Bohemian speech with numerous German words, and compares them to the "Jews who had married wives of Ashdod, and whose children spoke half in the speech of Ashdod."

Hus's merits as regards the development of his language are also very great. That language had indeed already, principally by Štitný, been raised to a level that rendered it available for the exposition of theological and philosophical matters. But the style of Hus contrasts favourably with that of his predecessors by its greater facility and simplicity. This may partly be attributed to the fact that Hus, particularly during the time of his exile from Prague, associated much with the humbler classes of the people, who, knowing no language but their own, naturally spoke it very purely and without interpolations from other languages. This spoken language was adopted by Hus for his writings. He indeed himself writes at the end of the Postilla, "That he who will read (my writings) may understand my Bohemian, let him know that I have written as I usually speak."

As already stated, the bibliography of Hus is as yet very uncertain, and it is not easy to fix the exact dates of his works. It may, however, be generally stated that his earliest Bohemian writings were composed in the years from 1406 to 1410, that his most important works in that language date from the last years of his life (1412-1415), and that the period of his exile from Prague was that of his greatest literary activity.

The earliest important Bohemian works of Hus are a series of Expositions (Výklad) dealing consecutively of Faith, the Ten Commandments, and the Lord's Prayer. Each Exposition is followed by a shorter, more condensed treatise dealing with the same subject as the longer one that precedes. Of these Expositions the first one, dealing of Faith, has most interest. It consists of a continuous comment on the different articles of the Apostle's creed. Hus writes: "We believe that the twelve Apostles, immediately after Christ's ascension to heaven, composed this creed. And as there were then twelve Apostles, besides Paul and Barnabas, who were called after the ascension of Jesus, thus, according to general opinion, each article was expounded by one particular Apostle. But be it known to you, that the learned do not agree as to what particular article each Apostle expounded." Hus then proceeds to attribute to each Apostle the exposition and defence of one of the articles, obviously following the method then usual at the theological disputations at universities in which he so frequently took part. In Chapter XVIII. the defence of the tenth article, which refers to the Holy Catholic Church, is attributed to St. Simon. It is interesting as containing some of the very distinctive ideas of Hus. He writes: "Every Christian must believe in the Holy Catholic Church. The reason is, that every Christian must love Christ, who is the husband of that Church, and that Church is Christ's spouse.... And as no one will honour his mother if he has no knowledge of her, therefore it is very necessary to know the Holy Church through faith, for ignorance of the Church causes many errors among the people. Therefore be it known to you that the first Bohemian who translated the Greek word ecclesia misunderstood that word; therefore he foolishly rendered it by the word 'church' or 'chapel,' as if he believed that the bride of Christ was a church made of stone or a chapel made of wood. But had he translated the word ecclesia by 'congregation,' then so many would not have erred. Others, again, err, saying that the Pope is the Holy Church; others, that it is the Cardinals with the Pope; while others, again, say all priests together, and yet others (say) all Christians together, constitute the Church.

"Therefore be it known to you that all men from Adam to the last man form one congregation, which God has divided into two; one division has been chosen (for salvation) from eternity, the other from eternity has been rejected, and it is known to God only which (division) each man belongs to. The first division is the universal community of saints, the second is the universal community of the damned. There can be no higher Church, according to God's will, than the first-named (community). It contains all the good, and the other all the evil, and yet these two (divisions) constitute one community, one assembly, just as sheep and goats form one herd, although the sheep are always in a way divided from the goats, and these from them. Therefore though ecclesia sometimes signifies a church of wood or stone, sometimes the Pope with the Cardinals, sometimes the priesthood generally, sometimes the whole community of Christians—as the Church of Prague may signify all Bohemians or a community only of good Christians—yet the Holy Catholic Church is the community of all those who have been chosen; that Church is called the bride of Christ, of whom it is written in the verses of Solomon, 'I am His bride, He has adorned me with a crown.'"