A religious purist, Jón made it his mission to uproot all remnants of paganism.

[1] These two events are distinguished in the Icelandic annals: Jón was not 'made a saint' by the Althing.

He was venerated primarily in the diocese of Hólar, and also at his birthplace, Breiðabólstaður in Fljótshlíð; relics were preserved at both these places.

A Latin life (vita) about St. Jón was probably written by the monk Gunnlaugr Leifsson of the monastery at Þingeyrar in the early thirteenth century.

The Latin original has not survived, but it was translated into Icelandic shortly after its composition and revised on subsequent occasions.