He was one of the three men who were tasked by Jón to travel to Denmark in 1542 negotiate before King Christian III whether Iceland would remain Catholic or become Lutheran.

During his stay in Copenhagen, Ólafur was swayed for the Reformation but he did not break with the Catholic leader Jón initially.

[1] Over the years, Ólafur became more disenchanted with the Catholic Church and more outspoken in favor of Luther's teaching, causing Jón to banish him in 1549.

Ólafur fled to Copenhagen and received the approval of the king to return to Iceland in 1551 to assume the role of bishop of Hólar, a position he held until his death in 1569.

[2] To this end, he continued Hólar's printing activities, publishing several books including translations of several hymns into Icelandic.