From 1826 to 1903, about 80% of the students of Seinai Theological Seminary were ethnic Lithuanians, and Lithuanian was their or their parents’ native language. The question about Lithuanian activities of the Lithuanian students at the seminary is therefore well founded. During first decades of its existence, national consciousness of the Lithuanians was not relevant. For performing pastoral work in Lithuanian parishes, the Lithuanian brought from parental home was sufficient. Using the Lithuanian language at Seinai Theological Seminary was stimulated by the reforms of Bishop K. I. Łubieński and encouragement of Professor Stanisław Jamiołkowski. First of all, the use of Lithuanian manifested itself through the singing of Lithuanian folk songs. Singing Lithuanian songs stressed the ethnic difference between the Lithuanian and Polish students of the seminary. Officially, the Lithuanian language was not taught at the seminary until 1904. For this reason, Lithuanian students started learning Lithuanian secretly: they realised they would need it in their pastoral work. Seminary students spoke Lithuanian among themselves, thus demonstrating their national awareness, but they also learned Polish at the seminary. The students’ Lithuanian activities should be viewed in the context of Lithuanian nationalism. National revival was raising specific requirements to the Church and it was important that the seminary trained future clergymen to meet the demands of the public. The students engaged in Lithuanian activities through participation in a secret association of future Lithuanian priests. One of the forms of its activities was distribution of the banned Lithuanian press. The students not only distributed banned literature but also contributed to its printing and publishing: they produced hand-written newspapers in the seminary and wrote articles, first for illegal publications and later, after the ban on the Lithuanian press was lifted, for legally published periodicals.