40 You have Twelve Apostles, witnesses of the Cross; and the whole earth, and the world of men who believe in Him who hung thereon. Let your very presence here now persuade you of the power of the Crucified. For who now brought you to this assembly? What soldiers? With what bonds were you constrained? What sentence held you fast here now? Nay, it was the Trophy of salvation, the Cross of Jesus that brought you all together. It was this that enslaved the Persians, and tamed the Scythians; this that gave to the Egyptians, for cats and dogs and their manifold errors, the knowledge of God; this, that to this day heals diseases; that to this day drives away devils, and overthrows the juggleries of drugs and charms.
Source: Catechetical Lectures (New Advent)