Authoritatively

The Latin language has always been held in very high esteem by the Catholic Church and by the Roman Pontiffs. They have assiduously encouraged the knowledge and dissemination of Latin, adopting it as the Church’s language, capable of passing on the Gospel message throughout the world. This is authoritatively stated by the Apostolic Constitution Veterum Sapientia of my Predecessor, Blessed John XXIII.

He has, of course, the right to speak authoritatively, and he laughs at my theory that there was a crack in Pansay's head and a little bit of the Dark World came through and pressed him to death.

The inability of Trump's own spokespeople to speak authoritatively on the president's thinking and actions -- a challenge even Trump himself has acknowledged -- has left the White House with an enormous credibility gap, and has tarnished the reputations of many of its most visible spokespeople.