affirmation - noun

a statement asserting the existence or the truth of something

the act of affirming or asserting or stating something

(religion) a solemn declaration that serves the same purpose as an oath (if an oath is objectionable to the person on religious or ethical grounds)

a judgment by a higher court that the judgment of a lower court was correct and should stand

affirmation - thesaurus

assertion   avouchment   avowal   statement