In an article (IIa IIae, 1, 10) about the pope’s authority to “ordain” (ordinare) an authoritative creed (symbolum fidei), Thomas argues that he pope does have this power, but makes the case thus:
editio symboli facta est in synodo generali. Sed huiusmodi synodus auctoritate solius summi pontificis potest congregari…Ergo editio symboli ad auctoritatem summi pontificis pertinet (sed contra).
“The edition of the symbol is made in a general synod. But in this manner a synod is able to be convened by only by the authority of the Supreme Pontiff…Therefore, the edition of the symbol pertains to the authority of the Supreme Pontiff.”
That is quite an elegant linkage (dare we say subordination?) of the pope’s personal magisterial authority to his authority within an ecumenical council of his fellow bishops. How compatible is Thomas’s formulation with that of Vatican I? Can we distinguish the revision or propagation of binding faith statements from the promulgation of new dogma ex cathedra?