the act of certifying or bestowing a franchise on

The act of testifying by means of a written statement; a written statement given as proof of facts, etc.

But that the very first act of Angela's new life should be to influence her husband in the direction of his weakness, and, as it seemed, of her own good comfort- what was this, indeed, but a brilliant certification of all the grounds of his own attack?... – Angela's Business by Henry Sydnor Harrison