Avouch
From BiblePortal Wikipedia
Webster's Dictionary [1]
(1): (n.) Evidence; declaration.
(2): (v. t.) To acknowledge deliberately; to admit; to confess; to sanction.
(3): (v. t.) To appeal to; to cite or claim as authority.
(4): (v. t.) To maintain a just or true; to vouch for.
(5): (v. t.) To declare or assert positively and as matter of fact; to affirm openly.
Hastings' Dictionary of the Bible [2]
Avouch . This word, now obsolete except in legal phrases, means to acknowledge .
International Standard Bible Encyclopedia [3]
a - vouch ´: In English Versions of the Bible only in Deuteronomy 26:17 , Deuteronomy 26:18 , in the sense of "to confess," "avow," "publicly and solemnly declare." The Hebrew form is likewise unique (Hiph. of 'āmar ).