Pope Benedict XIV pointed out (1) that we are obliged to venerate an exposed Host (cultum negari non posse hostiae ad venerationem expositae). But (2): although it is de fide that consecrated Hosts have been transubstantiated, (3) it is not de fide that this particular host actually was, as a matter of History, certainly consecrated (licet de fide non sit esse consecratam).
You see what he means
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