a-vouch': In English Versions of the Bible only in Dt 26:17,18, in the sense of "to confess," "avow," "publicly and solemnly declare." The Hebrew form is likewise unique (Hiph. of 'amar).
Bibliography Information Orr, James, M.A., D.D. General Editor. "Definition for 'AVOUCH'". "International Standard Bible Encyclopedia". bible-history.com - ISBE; 1915.