In God there is one divine nature. In God there are three persons, God the Father, God the Son and God the Holy Spirit. A nature answers the question of what something or someone is. A person answers the question of who someone is. If we were to ask a young boy what he is, he would answer “I am a boy”. If we were to ask him who he is, he would answer “I am Jimmy Smith”, or whatever his name may be. If we were to ask God what he is, he would answer “I am God”. If we were to ask God who he is, he would answer, “I am God the Father, God the Son, God the Holy spirit”.
The mystery of the Trinity can only be known through divine revelation. It is not a knowledge that could have been arrived at by human reason alone. “Now it came to pass when all the people had been baptized and being in prayer, that heaven was opened, and the Holy Spirit descended upon Him in bodily form as a dove, and a voice came from heaven, “Thou art my beloved Son, in thee I am well pleased”. (Luke 3, 21-22) Although, the word “Trinity” is not specifically mentioned in the Bible, the reality of the Trinity is revealed nonetheless.
In Meditating upon the mystery of the Blessed Trinity we may consider that God, having made us in His own image, gave us the faculties of intellect, will, and memory. Together these are the trinitarian faculties that reflect the likeness of God’s image in which we are made. Consider also that the family is also an image of the Blessed Trinity, with the Holy Family of Jesus, Mary and Joseph being a most pure reflection. The union of the Trinity is reflected in these images and it is in union with the Trinity that we are all called. It was from the beginning, as it were, a “family affair”, and now, the call to union with the same “family” of the Blessed Trinity, is extended to all humanity.