1. The mistery of the Holy Trinity
BALEN, Hendrick van
Holy Trinity
1620s
Oil on panel
Sint-Jacobskerk, Antwerp
The mistery of the Holy Trinity 05
©Fr. Mark Emman H. Sese

2. Compendium of the Catechism
44. What is the central mystery of Christian faith and life?  
The central mystery of Christian faith and life is the mystery of the Most Blessed Trinity. Christians are baptized in the name of the Father and of the Son and of the Holy Spirit.

3. Introduction
The most important divine secret of the faith that Jesus Christ revealed to us: the mystery of the Holy Trinity.
The fact that God is one in essence and three in persons is the revelation of His intimate life.
We must try to find out about it and experience it.
The Creed is the explanation of the mystery of the Holy Trinity.
The most important divine secret of the faith that Jesus Christ revealed to us is the mystery of the Holy Trinity. Jesus spoke of his Father and the Holy Spirit as one and the same God; and He affirmed that I and the Father are one (John 10:30), because He is the Son of God. The Father, the Son and the Holy Spirit are one God – not three gods – because they have the same divine nature, although they are really three distinct Persons.
The fact that God is one in essence and three in persons is the revelation of His intimate life, the greatest and most profound of all mysteries; it is the fundamental mystery of our faith and our Christian life. We must try to find out about it and experience it. The Creed is the explanation of the mystery of the Holy Trinity, of who God is and what He has done for His creatures by creating them, by redeeming them and by sanctifying them.
BECCAFUMI, Domenico
Trinity (detail)
1513
Oil on wood
Pinacoteca Nazionale, Siena

4. Main ideas
©Fr. Mark Emman H. Sese

5. 1. The Trinity, the mystery of one God and three truly different Persons
Misteries are beyond us, we must try to find out more and more about them so that our faith may be strong and operative.
The mystery of the Holy Trinity:
in God there is only one essence and three distinct Persons: Father, Son and Holy Spirit, each of which is God, without being three Gods but rather the one and true God.
We may compare this mystery with the sun:
the sun is in the sky and produces light and heat: light and heat are not distinct from the sun.
We shall never be able to understand mysteries because we are limited in our scope to do so and they are beyond us; however, we must try to find out more and more about them so that our faith may be strong and operative.
The mystery of the Holy Trinity consists of the fact that in God there is only one essence and three distinct Persons: Father, Son and Holy Spirit, each of whom is God, without being three Gods but rather the one and true God.
We may compare this mystery with the sun: the sun is in the sky and produces light and heat: light and heat are not distinct from the sun. And so something similar occurs with the Trinity: the Son and the Holy Spirit are equal in nature to the Father, but together are one God. The Father is God, the Son is God, and the Holy Spirit is God. Three Persons in One God.

6. 2. Salvation, work of the Trinity
Creation is attributed to the Father; Redemption, to the Son, and sanctification to the Holy Spirit: we attribute distinctive works to each Person of the Holy Trinity, but all Their works are made by God, both One and Three.
That is why, when we thank God for everything He has done for us, we must thank God the Father, God the Son and God the Holy Spirit.
All things have been created by God, both One and Three. God created the world, although creation is attributed to the Father; God made Redemption, although only the second Person – the Son – became a man and died on the cross; God sanctifies us, although we attribute sanctification to the Holy Spirit. That is why, when we thank God for everything He has done for us, we must thank God the Father, God the Son and God the Holy Spirit.
CARRACCI, Lodovico
The Trinity with the Dead Christ
c. 1590
Oil on canvas, 173 x 127 cm
Pinacoteca, Vatican

7. 3. Inhabitation of the Trinity in the soul in grace
The man who lives in the state of grace is a living temple of the Most Holy Trinity (cf. John 14:23).
From the day we are baptized, if we do not reject Him by mortal sin, it is God who is in our heart: God the Father, God the Son and God the Holy Spirit.
We have God inside us to sanctify us, to help us, to be with us, because He loves us.
Although it is not easy to explain, it is a truth that fills us with happiness to know that he who lives in the state of grace is a living temple of the Most Holy Trinity (cf. John 14:23). From the day we are baptized, if we do not reject Him through mortal sin, it is God who is in our heart: God the Father, God the Son and God the Holy Spirit.
We have God within us to sanctify us, to help us, to be with us, because He loves us. We may speak with the Most Holy Trinity in the certain knowledge that we are listened to and that our prayers are answered. We know this through faith and, although we may not see it or feel it, we know that it is true. When we are in the state of grace, we are temples of God.
MASACCIO
The Baptism of the Neophytes
Fresco, 255 x 162 cm
Cappella Brancacci, Santa Maria del Carmine, Florence

8. 4. In heaven we shall see the Holy Trinity
The great prize of heaven consists of seeing God, contemplating, praising, loving and enjoying the Most Holy Trinity for all eternity:
All the greatness, all the beauty, all the goodness of God devoted to us His poor creatures.
In heaven the soul shall have the chance to see what Moses wished to see on Earth: the majesty of God.
Here on Earth we know that God is in our soul through grace, and that Christian life is a struggle against sin. If we are worshippers and we are strengthened by the love of God more and more, we shall be granted the greatest thing we can attain: seeing Him face to face, as He is. The great prize of heaven consists of seeing God, contemplating, praising, loving and enjoying the Most Holy Trinity for all eternity. All the greatness, all the beauty, all the goodness of God devoted to us His poor creatures.
On Mt. Sinai, Moses asked to see the face of God, and the Lord answered that no man can see Him without dying. Nevertheless, in heaven the soul shall have the chance to see what Moses wished to see on Earth: the majesty of God.
LÓPEZ Y PORTANA, Vincente
Adoration of the Trinity
Oil on canvas, 112 x 80 cm
Private collection

9. 5. We must praise the Holy Trinity
God loves us in an incredible way. So much love must be returned by continually praising the Trinity.
We profess faith in the Holy Trinity
when we make the sign of the Cross, saying “in the name of the Father, and of the Son and of the Holy Spirit,”
when praying “Glory Be to the Father, and to the Son and to the Holy Spirit”;
when we recite the Glory Be to the Father or the Creed during Holy Mass.
Through faith we realize that being Christian is something wonderful. God loves us in an incredible way: He created us for love, He redeemed our sins by dying for us, He lives in our soul in the state of grace, and He prepares us – if we are faithful - for eternal life. He has given us the Church and the sacraments so that we may easily know what we have to do as good Christians, becoming holier each day. So much love must be returned by continually praising the Trinity.
We profess faith in the Holy Trinity when we make the sign of the Cross, saying “in the name of the Father, the Son and the Holy Spirit,” when praying “Glory Be to the Father, the Son and the Holy Spirit, " when we recite the Glory Be to the Father or the Creed during Holy Mass, and at the end of the Eucharistic Prayer. We should try to say these prayers and praise the Trinity with true conscious faith so that our life may be a continuous praise of God the Father, God the Son and God the Holy Spirit.
GRECO, El
The Trinity
1577
Oil on canvas, 300 x 179 cm
Museo del Prado, Madrid

10. Resolutions for Christian life
©Fr. Mark Emman H. Sese

11. Resolutions to move forward
To learn the Creed and to pray it with devotion.
To consider that the Holy Trinity –God Himself- inhabits in the soul in the state of grace, and that living in grace is the only thing that really matters.