Today we celebrate the mystery of God, that has been revealed to us in salvation history as the Most Holy Trinity: Father, Son and Holy Spirit. To contemplate and adore something of that infinite abyss of love and of communion that is God, we draw close with faith to the pages of Scripture. The Bible, in effect, helps us to overcome certain theological speculations, abstract and theoretical, about the Trinity, and to purify the deformed images of God that we have gone on fabricating throughout life. The Solemnity of the Most Holy Trinity is the celebration of God that has become present in history, "taking to himself one nation from the midst of another by ordeals, signs and wonders" (Dt 4,34) (first reading); it is the celebration of God that is present in the most intimate depth of man, making him a "temple of the Spirit" and "son of God" (Rm 8,9.14) (second reading); and, finally, is the celebration of God present in the Church, called to announce it to all peoples through catechesis, the compromise of charity and the sacraments (Mt 28,19-20) (gospel).

The first reading (Dt 4,32-34.39-40) forms part of the reflection of the Deuteronomic School, which defines always the attributes of God through the reading of his great actions in history. Israel arrives at the profession of faith in the only God and to the theological formulation of a singular bond between Yahweh and Israel, not by means of cold reflections and theories, but through the mediation of all that God has done for his people in history. The memory of the liberation from slavery in Egypt, "with mighty hand and outstretched arm" (v. 34.37), the commemoration of the experience of the covenant at Sinai, when God "from one end of heaven to the other let his voice be heard to show you there is no other God" (vv. 33.35), and the invocation of the gratuitous gift of the promised land, "dispossessing for you nations who were larger and stronger than you" (v. 38), make the author of Deuteronomy conclude: "Hence, grasp this today and meditate on it carefully: Yahweh is the true God, in heaven above as on earth beneath, he and no other" (v. 39). All of this demonstrates that biblical faith is founded in a history, that we cannot forget, but that we have to continuously make present. God is for us that which he has done and continues doing for us. The God of the Bible has presented himself with a singular name: "I Am who am"; that is, as he that reveals his being through that which he does in each moment for the people and for each man and woman. God has not revealed himself to us through theoretical and abstract concepts, but by means of his saving acts in history; therefore, neither our response of faith can be limited to accepting some dogmatic formulas, but it demands a compromise of all of our existence, which – at the same time – will give meaning to the truths in which we believe.

The second reading (Rm 8, 14-17) forms part of the Pauline reflection about the action of the Holy Spirit in the life of the Christian. To understand the text that the liturgy presents us with it is useful to use to category of "journey." The Spirit guides the Christian on the journey of history, as Yahweh guided Israel in the desert, "going ahead of you on the journey by night in the fire to light your path, and in the cloud by day" (Dt 1,33). Now also, in the desert of life and in the happenings of history, "everyone moved by the Spirit is a son of God" (Rm 8,14). While we journey, the Spirit makes us participate in the life of the Son, to the point that we can direct ourselves to the Father with the familiarity with which Jesus did, not as slaves filled with fear, but as true sons and daughters: "Abba, Father" (v. 15). The Spirit, in effect, continuously"bears witness that we are sons of God" (v. 16). The grand witness of this divine filiation is the Spirit that diffused in us by the gift of charity reveals and communicates to us the fundamental quality of God: love. At the end of the journey, after the sufferings and tests of the present life, the same Spirit will introduce us into the glory of Christ, as "coheirs with Christ," "sharing his sufferings so as to share his glory" (v. 17). In synthesis, in the journey of the Christian life, the Spirit, leads us, makes as live, pray as sons of God, and at the end, will make us participate in the same glory of Christ.

The gospel (Mt 28,16-20) refers to the Easter apparition in Galilee with which concludes the gospel of Matthew, structured in three parts: the presentation of Christ, the mission and the promise of the presence of the Lord until the end of time. The background is a "mountain," biblical symbol that evokes a privileged space in which God revealed himself in the first covenant (cf. Ex 19; 1 K 19). The geographical indication makes reference above all to the history of Jesus, that from a mountain proclaims the beatitudes (Mt 5,1; 8,1), that went up to the mountain to pray in solitude (Mt 14,23), that seated on the mountain welcomed the multitudes and cured the sick (Mt 15,29), and that on a mountain had revealed himself to the disciples as the definitively sent by God (Mt 17,1.5). The last encounter and the last revelation of Jesus has place also on a mountain, symbolic space of the revelation and of the salvation of God.

(a) The presentation of Jesus. Treats of a solemn declaration of his absolute lordship over heaven and earth: "All authority in heaven and on earth has been given to me" (Mt 28,18). The passive formulation of the phrase indicates that Jesus has received the power from God’s part (Mt 11,27: "Everything has been entrusted to me by my Father"). The word "power" translates the Greek term exousía, that indicates the "power", the "right" and the "capacity" that characterizes the word and the work of Jesus to carry out the plan of the kingdom (Mt 7,29: "taught with exousía"; 9,6: "the Son of Man has exousía on earth to forgive sins"; 21,27: "nor will I tell you my exousía for acting like this"). Jesus Resurrected is Lord of heaven and earth, with the messianic power to transform human history and carry it to the fullness of God.

(b) The mission. Jesus orders his disciples: "Go, therefore, make disciples of all the nations; baptize them in the name of the Father and of the Son and of the Holy Spirit, and teach them to observe all the commands I gave you" (Mt 28,19-20). The mission of the Church appears without any type of limits of restrictions, destined to reach all men and women of earth. The verbs utilized are significant: "to go" suggests the dynamic of the Christian life and of the mission that has to characterize the disciples of Jesus; "to make disciples" indicates the witness in words and works, through which the announcement of Jesus is carried to others;"to baptize" evokes the sign by which man and women are configured radically with Christ Resurrected and the same sacramental activity of the Church that sanctifies earthly realities communicating to them divine life;"to observe" indicates the response of the believer, his or her full welcoming and obedience of the word of Jesus in daily life. The mission of the disciples, participants in the same Spirit of Christ, is the same mission for which the Son has been sent, that is, to take all to the Father.

(c) The presence of Jesus. It is the last word of Jesus in the gospel of Matthew. A promise that is source of trust and hope for the disciples. In the Old Testament, the phrase: "I will be with you," or "I will be with all of you," expresses the guarantee of a saving and active presence of God in favor of his chosen one and of his people (cf. Ex 3,12; Jer 1,8; Is 41,10; 43,5). Jesus, established as universal Lord through the resurrection, carries out to fullness this saving presence of God. He is "God-with-us." Effectively so, Matthew calls him this at the beginning of the gospel, calling on a text of Isaiah that refers to the messianic line of David (Mt 1,22-23; cf. Is 7,14). The presence of Jesus is not now limited by the same and time of Israel. It does not treat of a provisional presence either. The disciples realize the universal mission of Jesus under the sine of his consoling and comforting presence. The efficaciousness of the mission and the authority of the teaching of the apostles is founded on this presence of Jesus.

The Solemnity of the Most Holy Trinity is a provocation of our faith, so that we will rediscover each day with stupor and gratitude the "Name" of the Holy God: Father, Son and Holy Spirit. The election of Israel, in a gratuitous and loving way, reveals to us a God that intervenes in history to save the small and oppressed and that desires to live in their midst to communicate to them the fullness of his life. The presence of Yahweh in the midst of his people reaches its culminating point in Jesus Christ, the "Emmanuel," "God with us," that as source of life carries history to its omega point. All is work of the Spirit, the "éxtasis" of God, that creates the filiation and the glorification of the believer in Christ and transforms history into salvation and life. We will not be able to understand anything in an immediate and definitive way, the mystery of the Most Holy Trinity, but we are called to open ourselves up every day – even in the midst of doubt – to a greater penetration of his love and saving power. The experience of Godpasses by the incertitude of faith and supposes the constant search of the ways of the Lord in reality, to be able to discover continuously his authentic face and welcome his will in each moment. Our experience of God and our language about him will be always imperfect and limited while we live in this world. For this reason, we have need of a process of growth and of purification that carries us to destroy out ideas and our images of God, to adhere only to Him in faith.