Definition of "proclaimer"

You have in the merchant the shrewd calculator of probable contingencies; we shall see that we have in the prophet the absolute proclaimer of necessary and inevitable facts.

1858, John Cumming, Thy Word is Truth: an apology for Christianity, page 112

Though a herald and proclaimer of peace, he could fight stubbornly and passionately on the side of justice.

1910, Helen Keller, The Song of the Stone Wall‎