The Holy Rosary is a Trinitarian Prayer

One of the central tenets of the Roman Catholic Church is the Trinity, One God in Three Persons, Father, Son and Holy Spirit.  

 
In the Nicene Creed which dates from the Fourth Century A.D., we who believe profess this Trinitarian reality:  

 
“I believe in one God, the Father almighty…

I believe in one Lord Jesus Christ, the Only Begotten Son of God…

I believe in the Holy Spirit, the Lord, the giver of life, who proceeds from the Father and the Son…”

 
The Catechism of the Catholic Church declares “The mystery of the Most Holy Trinity is the central mystery of Christian faith and life. It is the mystery of God in himself. It is therefore the source of all the other mysteries of faith, the light that enlightens them (See paragraph 234).”

 
The reality of the Trinitarian nature of God (One God in Three Persons) is attested to in Scripture and in the authentic teachings of the Catholic Church.  Naturally, the Trinity is present in the Holy Rosary.  In essence, the Holy Rosary is a Trinitarian prayer in which all three Divine Persons are present and play an active role. Jesus the Son of God is present in all Twenty Mysteries of the Rosary with God the Father and God the Holy Spirit also appearing at key moments in this spiritual journey through the life of Jesus.

 
The very first Mystery, the Annunciation, features the Virgin Mary receiving a Heavenly messenger who informs her that she has been chosen to bear the Son of God.  Here in this Mystery is the conception of God the Son by God the Holy Spirit in the womb of Immaculate Mary.  

 
All three Divine Persons are present in the First Luminous Mystery – the Baptism of Jesus.  In this Mystery, God the Holy Spirit descends upon God the Son and God the Father declares “You are my beloved Son; with you I am well pleased”  (Mark 1:11).  

 
God the Father again speaks in the Fourth Mystery – the Transfiguration.  After Jesus is transfigured and converses with Moses and Elijah, God the Father says to the Apostles Peter, John and James (and through them to us):  “This is my beloved Son. Listen to him”  (Mark 9:7).  

 
At the Last Supper when Jesus institutes the Sacrament of the Holy Eucharist, Jesus also promises to send the Third Person of God to them.  As St. John records in his Gospel, Jesus tells his Apostles:  “The Advocate, the holy Spirit that the Father will send in my name—he will teach you everything and remind you of all that [I] told you”  (John 14:26).  

 
Jesus fulfills this promise in two ways.  First in the First Glorious Mystery (the Resurrection), the Risen Jesus appears to his Apostles, breathes on them and says “Receive the holy Spirit”   (John 20:21-22).  Then in the Third Glorious Mystery, God the Holy Spirit descends upon the Apostles and Mary at Pentecost (Acts of the Apostles 2:1-41). 

 
All Three Divine Persons are present in the Fourth and Fifth Glorious Mysteries, ie. the Assumption of Mary and the Crowning of Mary.  Both of these epic events occur in the Heaven in the presence of God the Father, Son and Holy Spirit.  

 
As one of the central tenets of the Catholic faith, the Trinitarian nature of God is rightfully included in one of the most important prayer devotions of the Catholic faith, the Holy Rosary.  Each person of God plays an important role in this devotion.  The participation of the Triune God is one further example of the rich spiritual complexity of the Holy Rosary.