He is the author of an Icelandic dictionary and a 1732 "Runologia", a treatise on runology. As in the fire of Copenhagen of 1728, the original manuscript of the "Heiðarvíga saga" was lost along with a recent copy made by Jón Grunnvíkingur, he wrote down a summary of the saga from memory, which is the only form in which the saga's contents survive today.