The sense of divine filiation, the effect of the gift of piety, moves us to treat God with the tenderness and affection of a good son with his father, and other men as brothers who belong to the same family.
The Old Testament manifests this gift in many ways, particularly in the prayer that the Chosen People constantly address to God: praise and petition; sentiments of adoration before the infinite divine greatness; intimate confidences, in which they expose in all simplicity to the heavenly Father their joys and anxieties, their hope.... In a particular way we find in the psalms all the feelings that overwhelm the soul in its trusting relationship with the Lord.
When the fullness of time came, Jesus Christ taught us the proper tone in which we should address God. When you pray, you are to say: Father ..... In all circumstances of life we should address God with this filial confidence: Father, Abba.... In various places in the New Testament the Holy Spirit has willed to leave us this Aramaic word: abba, which was the affectionate appellative with which the Hebrew children addressed their parents. This sentiment defines our position and directs our prayer before God: "He is not a distant being who looks indifferently upon the lot of men and women, their troubles, their struggles and their anxieties. He is a Father who loves his children to the point of sending the Word, the Second Person of the Most Holy Trinity, so that, becoming incarnate, he might die for us and redeem us. The same loving Father who now draws us gently to Himself through the action of the Holy Spirit who dwells in our hearts".
God wants us to treat him with complete trust, as little children in need. All our piety is nourished by this fact: we are children of God. And the Holy Spirit, through the gift of piety, teaches us and facilitates this trusting relationship of a child with his Father.
See what love the Father has shown us, that we are called children of God, and we are. "It seems as if after the words let us be called children of God, St. John paused for a long time, while his spirit penetrated deeply into the immensity of the love that the Father has given us, not limiting himself to simply calling us children of God, but making us his children in the truest sense. This is what makes St. John exclaim: and so we are!". The Apostle invites us to consider the immense good of the divine filiation that we receive with the grace of Baptism, and encourages us to second the action of the Holy Spirit who urges us to treat our Father God with ineffable trust and tenderness.
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