Ge-swerian

According to the Old English Dictionary:

ic -swerige, -swerge;

ge-swerian

p. -swór, -sweór, pl. -swóron; pp. -sworen [swerian to swear] To swear, take an oath; jūrāre :-- Ic ðæt geswerige þurh sunu Meotudes this I swear by the son of the Creator, Elen. Kmbl. 1368; El. 686. Ic geswerge I swear, Exon. 67 a; Th. 247, 17; Jul. 80. Swá ic geswór wið Drihten sīcut jūrāvit Domĭno, Ps. Th. 131, 2. Ðú geswóre Apollonio thou didst swear to Apollonius, Apol. Th. 23, 5. He befóran his fæder gesweór, ðæt he nǽfre ne wurde Rómána freónd he swore before his father that he would never become a friend of the Romans, Ors. 4, 8; Bos. 89, 25. Him betweonum geswóran they took an oath among themselves, 1, 11; Bos. 34, 37: 1, 14; Bos. 37, 16. ge-swerian