'Confirmed' in the Bible

How shall we escape, if we neglect so great salvation; which at the first began to be spoken by the Lord, and was confirmed unto us by them that heard him;

while God confirmed their witness with signs and wonders and various miracles and gifts of the Holy Spirit distributed according to his will.

Wherein God, willing more abundantly to shew unto the heirs of promise the immutability of his counsel, confirmed it by an oath:

(for those Levites who formerly became priests [received their office] without [its being confirmed by the taking of] an oath, but this One [was designated] with an oath through the One who said to Him,“The Lord has swornAnd will not change His mind or regret it,‘You (Christ) are a Priest forever’”).

with teachings manifold and strange be not carried about, for it is good that by grace the heart be confirmed, not with meats, in which they who were occupied were not profited;