14 We are then, it will be seen, very far from attributing to the Mother of God a productive power of grace - a power which belongs to God alone. Yet, since Mary carries it over all in holiness and union with Jesus Christ, and has been associated by Jesus Christ in the work of redemption, she merits for us de congruo , in the language of theologians, what Jesus Christ merits for us de condigno , and she is the supreme Minister of the distribution of graces. Jesus "sitteth on the right hand of the majesty on high" ( Hebrews i. b.). Mary sitteth at the right hand of her Son - a refuge so secure and a help so trusty against all dangers that we have nothing to fear or to despair of under her guidance, her patronage, her protection. (Pius IX. in Bull Ineffabilis ).
Source: Ad Diem Illum Laetissimum (Vatican.va)