[4][5] In Rosenius' home, religion was important; he received a religious education at an early age including the works of Martin Luther and Olov Svebilius.

Having read a translation of Erik Pontoppidan's Heller Glaubensspiegel, which states that even the most seemingly-zealous believer who knows the entire Bible and can even perform miracles can still go to hell without true faith, Rosenius was shaken and became sullen for some time.

[1][3] He planned to study theology in Uppsala, so to raise money for his education, he took a venia position through the Church of Sweden, a paid role which gave lay preachers the right to preach at certain parishes.

[2] Around this time, Rosenius first met traveling Reader lay preacher Maja-Lisa Söderlund while visiting his parents in the Burträsk area.

Söderlund was widely known in northern Västerbotten for her knowledge of the Bible and her ability to inspire hope in difficult times while the Conventicle Act severely restricted laymen's opportunities to preach outside the framework of the household.

[15] In 1838 Rosenius began his theological studies at Uppsala University but was forced to give them up after a year due to failing health and financial difficulties.

[16] Rosenius' conversations with Scott, in which he also analyzed the Bible, helped dispel his uncertainties and "made him understand the vital role of the Christian laymen and gave him a vision of unity across the denominational borders.

[18]The opportunity marked a significant moment in Rosenius' life: he abandoned his plans of becoming a priest and moved to Stockholm to work with Scott at the newly built Engelska kapellet (English Chapel) near Hötorget (Haymarket Square).

Rosenius traveled around Stockholm as a preacher and colporteur, preaching in homes and at times to the well-to-do in larger meeting rooms.

Lars Paul Esbjörn, later founder of the Augustana Evangelical Lutheran Church, also worked with Scott at this time and was influenced by Rosenius.

[3] That year, however, increasing public controversy and threats over Scott's preaching forced him to leave Sweden, and the English Chapel ceased operations.

[19] He became a leader in the growing religious revival of Sweden, traveling throughout the country, preaching both at private gatherings (conventicles) and in public halls.

Rosenius did face doubts at this time, however, stating in a letter to future bishop of the Diocese of Lund, Johan Henrik Thomander, that he felt "to preach and to be 'in the vineyard among the people', would be more his calling than writing, but that he is 'not fit to be a priest'.

On hearing Rosenius, preacher Paul Petter Waldenström described his preaching in his Norrland dialect as natural and down-to-earth, with "no pompous words, no grandiose claims".

The Swedish Evangelical Mission, intended to bring together the different revival groups, was formed by Hans Jacob Lundborg [sv] in 1856.

[26] Rosenius' Pietism, influenced by the Läsare (Reader) movement, the Herrnhuters (Moravian Brethren), and Methodism, retained key features of the northern Swedish religious revival – with the Bible as the Word of God, Lutheran objective atonement in Jesus Christ, and justification by grace alone at its core.

He was on friendly terms with the Herrnhuters and had much in common with the Finnish evangelist Fredrik Gabriel Hedberg, despite believing that he went too far in the direction of antinomianism.

He did not use Den svenska psalmboken, the Church of Sweden's hymnal, but rather song collections of a more personal religious nature, including those published by Oscar Ahnfelt.

[33]Rosenius' movement gained followers through the Mission Friends (Missionsvännerna) both within Sweden and abroad – particularly in Denmark (the Bornholmers)[34] and Norway, as well as among Scandinavian settlers in the American Midwest.

Among them was a lay preacher from Småland named Nicolaus Bergensköld, who immigrated to the United States in the 1860s and was a leader of the revivalist movement in the Scandinavian settlements of the American Midwest.

His works were held in high esteem and reprinted by Lutheran leaders such as Tuve Hasselquist, Olof Olsson, and John N.

[35] He was also friends with and influenced Anders Wiberg, Per Palmqvist, and Gustaf Palmquist, Lutherans who became Baptist pioneers in Sweden and the United States.

[36][37] He had a great impact on the religious development of Mathilda Foy, an early innovator of Sunday school in Sweden known for her charitable work, who was introduced to Rosenius by Theodore Hamberg, a missionary equally captivated by his preaching.

[1] Shortly after Rosenius' death, a large segment of his followers broke with his ecclesiastical views, led by Peter Paul Waldenström – his successor as publisher of Pietisten – and became separatists, founding the Swedish Mission Covenant.