Sentence:  This is brought out in the common religious ethos that prevails even in the denominationally diverse audiences at many secular semi-public and public occasions in the United States ; and it is evidenced in the prayers offered , in the frequent religious allusions , and in the <WSD>confirmation</WSD> of points on religious grounds . 
Meaning of the word marked with <WSD> tags:  additional proof that something that was believed (some fact or hypothesis or theory) is correct