An Etymological Dictionary of the German Language/opfern

by Friedrich Kluge

opfern, vb., from the equiv. MidHG. opfern, OHG. opfarôn, ‘to sacrifice’; so too OSax. offrón, Du. offeren, AS. offrian, ‘to sacrifice,’ whence E. to offer, under the influence of Fr. offrir. Introduced by the Church from Lat. offerre. With regard to the change of accent in Teut., comp. predigen, from praedicare, in which the verbal particle likewise assumed the accent. —