Spirituality of St Teresa Margaret Redi developed on her devotion to the Sacred Heart of Jesus. She lived in times when this devotion was spreading rapidly throughout the world, propagated by the Order of Jesuits and it is quite possible she was actually introduced to this devotion by her Jesuit uncle, Father Diego Redi. Devotion to the Sacred Heart brought young Sister Teresa to the mystical period of her spiritual life. In 1767, first time in her life, was seized with a type of rapture during recitation of the Divine office when the words from the first epistle of St John were chanted: "God is love, and he who dwells in love dwells in God and God in him." Although she was diligent not to manifest in any way the secrets of her hidden, interior life, she was so overwhelmed by the divine action that she went through the cloister so elated frequently repeating the words: "God is love" to herself. Other nuns were wondering at this peculiar behaviour and asked her why she repeated these words so often. The Saint, realising she had betrayed herself said: "Having heard them one Sunday at the little Chapter of Terce, I found such sweetness in them, and they made such an impression on me, that I must repeat them." One of her companion, Sister Teresa Maria Racasoli, said "Her face was flushed and her bearing was that of one beside himself" she "pronounced the words with feeling, in a high voice, with meaning". According to Saint spiritual Father and confessor, Father Ildefonse: "she was so enraptured by the words that she remained in a state of elation for several days,... and one can surmise that they had been accompanied by an extraordinary outpouring of God upon her soul. From that day it was obvious that she was making giant strides forward in the practice of virtues." Fr Gabriel of St Mary Magdalene, OCD who wrote a little treatise "From the Sacred Heart to the Trinity" about St Teresa spirituality, is convinced that the Saint was blessed by unitive grace that produced such profound effects as spoken of by St Teresa in the fifth and sixth mansions and by St John of the Cross in the twenty sixth stanza of the Spiritual Canticle. Remarkably, afterwards St Teresa Margaret lived in oblivion of everything else and in absorption with God, the signs marking the beginning of a new stage of her spiritual life. She was experiencing many lofty spiritual secrets that she confessed to Fr Ildefonse. She made him understand, without intending it, some wonderful concepts of the knowledge of God that she had been nourishing in her soul. Let us listen to her words: "charity is the same love with which God love Himself from all eternity, the Spirit of God Himself, which is life and His breath. Who is the Holy Spirit, the Third Person of the Blessed Trinity. And when it is said that he who dwells in charity dwells in God and God in him, the meaning is that he lives in the life of God and God, after a certain fashion, lives His life in him. becasue between them there is but one life, one charity, one God; in God this all by essence but in the creature by participation and grace; thus it is true that everything is held in common by lovers". Very beautiful description of the meaning of God's love!
Based upon "From the Sacred Heart to the Trinity" by Fr Gabriel of St Mary Magdalen, OCD