Catholic theologians insist that the difference is one of kind and not merely of degree; dulia and latria being as far apart as are the creature and the Creator. Leibniz, though a Protestant, recognizes the " discrimen infinitum atque immensum between the honour which is due to God and that which is shown to the saints, the one being called by theologians, after Augustine's example, latria, the other dulia"; and he further declares that this difference should "not only be inculcated in the minds of hearers and learners, but should also be manifested as far as possible by outward signs". A further distinction is made between dulia in the absolute sense, the honour paid to persons, and dulia in the relative sense, the honour paid to inanimate objects, such as images and relics. With regard to the saints, dulia includes veneration and invocation; the former being the honour paid directly to them, the latter having primarily in view the petitioner's advantage.
The special veneration due to the Blessed Virgin Mary.
Vatican II’s Dogmatic Constitution on the Church states: 66 “The various forms of piety towards the Mother of God, which the Church has approved within the limits of sound and orthodox doctrine, according to the dispositions and understanding of the faithful, ensure that while the mother is honored, the Son through whom all things have their being Col 1:15-16 and in whom it has pleased the Father that all fullness should dwell Col 1:19 is rightly known, loved and glorified and his commandments are observed.”
There are three levels of reverence that we in this life offer. Latria is reserved for God alone. Hyperdulia is reserved for the Blessed Virgin. Dulia is reserved for all the rest of the heavenly host.
Latria ( latreia ) in classical Greek originally meant "the state of a hired servant" (Aesch., "Prom.", 966), and so service generally. It is used especially for Divine service (Plato, "Apol.", 23 B). In Christian literature it came to have a technical sense for the supreme honour due to His servants, the angels and saints. This latter was styled "dulia". Etymologically, however, there is no reason why latria should be preferred to designate supreme honour; and indeed the two words were often used indiscriminately. The distinction is due to St. Augustine, who says: "Latria . . . ea dicitur servitus quae pertinet ad colendum Deum" ( City of God X.1).