This is another secret prayer of the deacon. The term, "secret prayer,” refers to how the prayer is said quietly, as if it was hidden; it does not mean no one else can know them apart from the deacon.
The beauty of the secret prayers is that they add a dimension of mystery to the liturgy. The liturgy is the foretaste of heaven. A lot of the symbolism found in the Mass is found in the Book of Revelations. Heaven, in a very short explanation, is unveiled intimacy with the Trinity. As St. John the Evangelist and St. Paul remind us, we will see Him face-to-face.
If you are trying to get someone's attention from far away, then you really have to project your voice. But if a friend is standing right next to you, then you can speak more quietly. Your conversation would not be heard by those around you. So, it is with the secret prayers. Some of the secret prayers of the deacon and the priest, like this one, happen at moments in the Liturgy when they are in close proximity to Christ. In regard to this prayer, it is spoken by the deacon to Christ, as Our Lord is present in the Gospels, the Word of God.
The prayer calls to mind the message Jesus was preaching when He went into towns. Our Lord preached the Gospel, that is, the Good News. And the Good News is this, repent and believe in the Gospel. Put another way, turn your life toward Jesus, because He wants to take away your sins. Our Lord wants to heal us from our wounds and relieve us from the burden of guilt. We are not called to live with the so-called, “Catholic guilt”. Jesus called you to live with, “Catholic Mercy.” The “Universal Mercy” which came from His pierced Heart.