Ge-costnes

According to the Old English Dictionary:

-ness, e;

ge-costnes

f. [costnes a temptation] A temptation, trial, proving; probātio :-- Se wæs of dæghwamlícre gecostnesse ðæs mynstres becom to áncerlífe qui de monastērii probātiōne ad heremītĭcam pervĕnĕrat vitam, Bd. 3,19; S. 549, 42. ge-costnes