Father Isydor Dolnytskyi was born on February 21, 1830 into a priestly family in the town of Zaliztsi (Brody region), where his father Ivan was the pastor.

At the end of 1845 when he was in the first class of the Ternopil gymnasium, Metropolitan Myikhaylo Levytskyy sent him to study at the Greek College of St. Athanasius in Rome. After returning to Galicia in 1856, Isydor was ordained a priest and assigned as an assistant at the Church of St. George in Lviv. In 1857 the Metropolitan named Fr. Isydor chaplain for the students at the College of St.. Athanasius in Rome. He defended his Doctorate in Theology, and from 1863 worked in the Committee, which prepared materials for the canonization of St. Josaphat Kuntsevych. Then Pope Pius IX named him his deacon, and on all feast days Isydor read the Gospel in Greek.

In 1877, Metropolitan Josyf Sembratovych recalled Fr. Isydor to Lviv and appointed him Spiritual Director and Professor of Liturgy and Church Music at the Lviv Theological Seminary. In 1885, Fr. Isydor founded there the Brotherhood of the "Entry of the Blessed Virgin into the Temple." He was also the Spiritual Guardian of the Basilian Sisters.

Isydor made a significant contribution to resolving ritual questions at the Lviv Synod in 1891. He wrote several tracts, which the Synod later adopted in its decision. He is the author of several Akathists, services and hymns, but definitely the greatest of his scholarly achievements was the publication of his "Liturgical Typikon" (Typyka, 1899), which is the liturgical ordo of the Ukrainian Greek Catholic Church.

His contemporaries said the following about Fr. Isydor: : “Well he was - “Dzyadzo”, Father Prelate - a man from a fairy tale almost, rather an eternal poet - happy, enthusiastic, always delighting in the creative effort , hard working, kind, affectionate, and above all forgiving, and self-sacrificial beyond measure, and unbelievably warm, soft - a saint, his whole life was just”.

When Fr Isydor died on March 22 1924 he was believed to be a saint. He is buried in the Lychakivskyy cemetery in the tomb of the Cathedral Chapter.