176 In the heart of the Church, the mediation of Mary, as our intercessor and mother, can only be understood as “a sharing in the one source, which is the mediation of Christ himself”, the sole Redeemer. For this reason, “the Church does not hesitate to profess the subordinate role of Mary”. Devotion to the heart of Mary in no way detracts from the sole worship due the heart of Christ, but rather increases it: “Mary’s function as mother of humanity in no way obscures or diminishes this unique mediation of Christ, but rather shows its power”. Thanks to the abundant graces streaming from the open side of Christ, in different ways the Church, the Virgin Mary and all believers become themselves streams of living water. In this way, Christ displays his glory in and through our littleness.
Source: Dilexit Nos (Vatican.va)