Jacob was born in 1372 in Stříbro (called Mies in German and Misa in Latin) near Pilsen in Bohemia (present-day Czech Republic). He studied at the University of Prague, receiving both bachelor's and the master's degrees in theology, and became pastor of the Church of St. Michael and an outspoken supporter of Jan Hus.
In 1410 he took part in the disputations regarding John Wycliffe, defending the latter against archiepiscopal condemnation. Where Wycliffe saw ecclesiastical property ownership as a capitulation to the anti-Christ, Jacob saw the restriction of the communion cup.[1]: 51 His study of Scripture and the Fathers led him to believe that withholding of the chalice in the administration of Holy Communion to the laity was an arbitrary measure of the Catholic Church.
Jacob taught that communion under both kinds was necessary for salvation,[2]: 180 or at least an obligation,[3]: 518 and that as a precept of Christ it could not be changed by the church. Only those who received the ultraquist (both kinds) communion belong to the church of Christ.[4]: 51
In 1414, he propounded and defended his views in a public disputation; and when Hus, at that time attending the Council of Constance in Konstanz before his arrest, accepted them to some degree, Jacob began to administer the chalice to his parishioners, in spite of the remonstrances of the bishop and the university. His example was quickly followed by other pastors in Prague.
The Fathers of the Council of Constance (1415) issued a decree, explaining that reception of Holy Communionunder both kinds was not necessary for salvation, though such reception in and of itself was not evil. What was at stake was not the inherent good or evil of the practice, but the practical implications such as irreverence toward, and misunderstandings about, Holy Communion and the authority of the church to develop or adjust sacramental practice.[5]: 180
Though Jacob would by no means submit, he was not removed from his office, perhaps because in other points, as, for instance, in the doctrine of purgatory, he agreed with the Catholic Church. During the last decade of his life Jacob was regarded as one of the foremost of the Utraquist theologians. He died in Prague on 9 August 1429.
E. H. Gillett, Life and Times of John Huss, i., chap. xviii., ii. chap. iii., Philadelphia, 1861; KL, ii, 1315;
Neander, Christian Church, v. 297, 331, 337, 338, 367;
Dvě staročeská utrakvistická díla Jakoubka ze Stříbra. K vydání připravili Mirek Čejka a Helena Krmíčková (= Opera Universitatis Masarykianae Brunensis, Facultas Philosophica, 379). Brno (Masarykova univerzita) 2009, 140 pp. ISBN978-80-210-4843-0 [The book presents two hitherto unedited Old Czech Utraquist works by Jacob of Mies: O Boží krvi (On God's Blood) and Zpráva, jak Sněm konstantský o svátosti večeře Kristovy nařídil (Account on the Council of Constance's decision about Christ's supper).]
This article incorporates text from a publication now in the public domain: Jackson, Samuel Macauley, ed. (1914). New Schaff–Herzog Encyclopedia of Religious Knowledge (third ed.). London and New York: Funk and Wagnalls. 