The Baltimore Catechism Explained | Lesson 3: On the Unity and Trinity of God

Our Lady of the Rosary Family Catechism

Fr. Anthony Pillari JCL, MCL, STD

Lesson 3: On the Unity and Trinity of God

Welcome to the third lesson of Our Lady of the Rosary Family Catechism – On the Unity and Trinity of God. In the name of the Father, and of the Son, and of the Holy Ghost. Amen. O Jesus, I choose to live this day, for love of Thee, for the conversion of sinners, and in reparation for the sins committed against the Immaculate Heart of Mary. Amen.

In our last lesson we began to learn about God and His perfections. Today we will learn about the unity and Trinity of God. That is, we will begin learning about a mystery that we can only know because God has revealed it. We can only know it because God has taught it – that He is three Persons in one God. Listen to what happened when Jesus came to John the Baptist in the River Jordan and gave us a glimpse of the Holy Trinity.

John the Baptist, the cousin of our Lord, had been given the mission of preparing people for the coming of the Messiah. He fasted and prayed a lot, wearing camel’s hair for clothing and eating only honey and wild locusts. He preached a baptism of repentance and called people to turn from their sinful lives. Many came to him from all over Judea to be baptized in the River Jordan. He preached to the people saying, After me someone mightier than I is coming, whose sandals I am not worthy to carry. He will baptize you with the Holy Ghost and with fire." Then John saw Jesus coming to him, and he cried out, "Behold, the Lamb of God, behold Him Who takes away the sin of the world. (John 1:29) At first, John refused to baptize our Lord saying, "I ought to be baptized by You, and You come to me?"

But Jesus insisted that John should baptize Him, for this was part of the Father’s plans. And so, John baptized our Lord in the River Jordan. And as Jesus was coming up out of the water, John saw the heavens opened, and saw the Holy Ghost descending upon Him in the form of a dove and remaining on Jesus; and a voice from heaven spoke saying, "This is my beloved Son with whom I am well pleased."

We see hear a glimpse of each of the Persons of the Holy Trinity. The Son that is Jesus being baptized; the Father who speaks from Heaven; and the Holy Ghost who descends in the form of a dove. Now let us look at today’s questions:

Q. Is there but one God?

A. Yes; there is but one God.

Q. Why can there be but one God?

A. There can be but one God because God, being supreme and infinite, cannot have an equal.

Two things, or two people, are equal when they have exactly the same abilities – they’re just as good, neither one is better than the other. You could say that one pen is the equal of another if it is just as nice and will write just as well. Or one car mechanic is the equal of another if he can fix cars equally as well. Or two boys are equal in their studies if they receive exactly the same scores on their tests.

As we saw in the last lesson, every goodness or perfection in the world comes from God, and exists in God in a much greater way. That is why we say that God is infinitely perfect. Any good quality that we see in someone on the earth, God has that quality in a much, much greater way. So much so that it would be impossible to ever find someone better. This impossibility of there being anyone better, or even equal to God, is what we mean by saying that God is supreme. He is the best, the highest. He holds all authority and power in His hands. Any legitimate power and authority on earth comes from God. When we disobey our parents, or superiors who are placed over us, we disobey God Himself.

Now these next questions of the Catechism speak of the great mystery of the Holy Trinity. I will first give you all of them. So, don’t worry if you don’t understand them at first (in fact, you probably won’t). We’ll look at them in some detail in just a moment. Are you ready? If you keep in mind the sign of the cross you will easily remember the names of the three Persons of the Trinity. So let us make the sign of the cross together, remembering that the words Holy Ghost, or Holy Spirit mean the same thing; but that in these lessons we are using the older form, that is Holy Ghost – the one that was used by everyone at the time of the children of Fatima. In the name of the Father, and of the Son, and of the Holy Ghost. Amen.

Q. How many persons are there in God?

A. In God there are three Divine persons, really distinct, and equal in all things – the Father, the Son, and the Holy Ghost.

Q. Is the Father God?

A. The Father is God and the first Person of the Blessed Trinity.

Q. Is the Son God?

A. The Son is God and the second Person of the Blessed Trinity.

Q. Is the Holy Ghost God?

A. The Holy Ghost is God and the third Person of the Blessed Trinity.

Q. What do you mean by the Blessed Trinity?

A. By the Blessed Trinity I mean one God in three Divine Persons.

Q. Are the three Divine Persons equal in all things?

A. The three Divine Persons are equal in all things.

Q. Are the three Divine Persons one and the same God?

A. The three Divine Persons are one and the same God, having one and the same Divine nature and substance.

Q. Can we fully understand how the three Divine Persons are one and the same God?

A. We cannot fully understand how the three Divine Persons are one and the same God, because this is a mystery.

Q. What is a mystery?

A. A mystery is a truth which we cannot fully understand.

What do we mean by the word Trinity? Well, the word unity means to be one. Trinity means three in one. When we say the Trinity, we mean God Who is three Persons in one God. All three Divine Persons have always existed. So even though the Son comes from the Father, He does so in a different way from how sons come from fathers on the earth. On earth a father is always older than his son. So, you might think that in the Trinity, if there’s the Father and the Son, then that must mean that the Father is older than the Son. But this is not so.

God the Father, God the Son, and God the Holy Ghost, have existed, all three of them, from all eternity. They’ve always existed. One did not exist before the other. God the Son is just as old as God the Father. And the same is true for the Holy Ghost.

To help you understand, think for a moment about fire. When you start a fire, the fire never exists without right away causing heat. As soon as there’s fire immediately there’s heat. The fire is giving off heat. You never have fire, and then five minutes later, it begins giving heat. So also, in God, God the Father never exists without the Son coming forth from Him. They never exist without the Holy Ghost coming forth from Them. They always exist together. The difference with God compared to fire is that fire has a beginning. We start the fire. But God never starts, He has always existed. But the fire gives us a small image of part of this mystery.

The three Divine Persons are also distinct, meaning that they are not mixed up or mingled together. Like when you mix apple and orange juice in the same glass, if you’ve ever tried that. If you mix apple and orange juice together, it is all mixed up and it becomes a different sort of juice, all mixed up together. Well, the Trinity is not like that. The Father, and the Son, and the Holy Ghost are three distinct Persons. And yet, They share the same nature and substance. Let’s look now at what those two words mean. First of all, the word nature.

Say you have five friends, each of whom has a dog. So, when you go to their houses, you get to know their dogs. Each of the dogs is a little bit different, but each of them has the nature of a dog. That is, dogs can bark, they can eat dog food, they can run, they can sleep, and so forth. All dogs have the same nature, which is different from, for example, human nature. All men and women have the same nature, even though they’re different people and different personalities, they all have the nature. They all have certain common qualities, especially the ability to think, the ability to love, the ability to make free choices.

So, if there are seven people in your family, they have different personalities – but all seven have the same human nature – even though they’re different persons. So also, in God, each of the Divine Persons has the same nature – the Divine nature; the nature of being God. But the most mysterious thing about God is that He is not only three Persons with the same Divine nature, but that all three Persons have the same substance.

What does that mean? As Jesus tells us in the Gospel, He says, "The Father and I are one" (John 10:30). That is, they are one in being. Different human persons, for example, your neighbors or your friends, are not one in being. One of your neighbors could die, but the others would keep on existing. Each one exists independently from the others.

But in God, this is not so. The Father, the Son, and the Holy Ghost are so completely one that they are one substance, one in being. This is a great mystery that would take too long to speak about further here. But we can trust Jesus when He says, "The Father and I are one." That is what we mean by saying that each member of the Trinity has the same substance. For the moment, just try to remember the phrase: "The three Divine Persons are one and the same God, having one and the same Divine nature and substance."

We cannot fully understand how the three Divine Persons are one and the same God because this is a mystery. As we learned in the first lesson, although we have the gift of reason and we can understand some things, and by studying, we can learn many things; there are many more things that God Himself has to teach us that we can never learn by ourselves, only God can reveal [them] to us. This is the case with the Holy Trinity. We can only partly understand it.

We can understand the concept of one God. And we know what three persons are on the earth. But how these two things go together in God, three Persons in one God, is the part we do not understand. This is the mystery. A mystery is precisely a truth we cannot fully understand. Each mystery of our faith is a revealed truth, one made known to us by God. We know that whatever God reveals is true, even if we cannot understand it.

Let us take an example. If you’ve ever been to the ocean, you observe what is called the tide; that at one point of the day, the ocean’s water comes in and covers more of the beach. At another point in the day, the water only comes in a little, leaving much more of the beach uncovered. You may have asked your father or mother, or your teacher, "What caused the tide?" If so, they would have explained to you that it was due to the moon’s gravitational pull, and the different position of the moon at different times of the day. Your father and mother, and your teacher, know things which for you are still mysteries. That is to say hidden things.

Then there are other scholars or professors who are even more expert in certain subjects than your parents or your teacher. They teach us what we do not have the time to study, or the ability to understand. Yet even they cannot explain everything. Only our good God, who does know everything, can act as a perfect father and teacher for us. He taught us things that we could never have known without His teaching.

God’s teaching is called revelation. He teaches us about who He is, about what He has done for us, and about the path to heaven. These things that God reveals to us, but that we cannot fully understand, we call mysteries.

Now, wouldn’t you consider a boy foolish if the boy refused to believe the explanation of his father or teacher about the tides. If he saw the ocean water coming in further, coming in a little bit, and his teacher or father said, "Oh, that’s because of the moon. The moon is in different places and that’s what causes the tides." The boy says, "No. I haven’t seen it or studied it so I’m not gonna accept it. It must not be true, or I’m not gonna think it’s true. I don’t trust you. That would be a rather silly thing to do. Or, if he refused to believe anything he couldn’t prove himself, even if his father or teacher taught him.

So also, if we refuse, if you refuse to believe everything that you do not understand, you shall soon believe and know very little about the most import things in life. About God, about what He has done for us, and about the path to heaven. Finally, if this lesson was difficult don’t worry. The Trinity is one of the most difficult mysteries in the Catechism. Thankfully, in addition to His teachings in scripture, God has performed many miracles to confirm that the Catholic faith is true.

Today, I would like to share with you a miracle from a saint that lived not so long ago. Saint Pio of Pietrelcina, also known by many as Padre Pio, was a Franciscan religious, and a priest who lived during the 20^th century. He spent the majority of his life in the Capuchin monastery of San Giovanni Rotondo, Italy, where he lived for over 50 years until his death in 1968. Padre Pio was blessed with many mystical and extraordinary gifts from God. Like Blessed Mary of Ágreda, he was able to bilocate, and often appeared in two places at the same time.

On one such occasion, he prevented the bombing of San Giovanni Rotondo during World War II by appearing in midair, high up in the sky, right in front of the American fighter jets which were loaded with bombs. The pilots were shocked. Seeing this priest in a brown Franciscan habit floating in the air in front of them with his arms outstretched. I don’t know if his arms were outstretched like this, saying "Stop", or maybe his arms were outstretched like this, in the form of a cross, but he was floating in the air above them with his arms outstretched. And so, the pilots were unable to drop the bombs, they were so socked. And San Giovanni Rotondo was preserved.

Among many other miraculous gifts, Padre Pio often saw his guardian angel, and had visions of our Lady and our Lord. He even received miraculously the wounds our Lord suffered on the cross so that he had to cover his hands with bandages because they bled. He had wounds in the palms of hands that bled, so he had to cover them up with bandages, and also in his feet and his side. This is called the stigmata, which I’ll tell you a bit more about in a future lesson.

St. Pio also worked hard to keep people close to the sacraments. He often spent up to 15 hours a day in the confessional, hearing confessions of those who had traveled from all over the world. In fact, Padre Pio had the gift of reading souls. That is, he was able to see inside the hearts of people. He would be aware of their sins, knowing whether they were truly sorry for them, and whether or not they were lying or concealing their sins. On many occasions, those who came to confession reported that when they entered the confessional, they were so nervous that they were unable to speak. So, Padre Pio would speak for them, listing all of their sins with great precision – even if these sins were from many years ago, quite hidden, and even forgotten by the one confessing.

On one occasion, a young man went to confess to St. Pio. After he had finished confessing his sins, he fell silent. The young man thought he had finished his confession, but he had forgotten a sin. An important sin. St. Pio could see this; he could see it was on his soul. So, Padre Pio revealed to him that he could not miss mass on holy days because this was a mortal sin. The young man then suddenly remembered that he had missed mass one Sunday and quickly confessed this forgotten sin.

Also, sometimes the one confessing would confess in his own language. So, they would come to confession and speak English or German or French, and Padre Pio didn’t know any of these languages. But miraculously, he would be able to understand them when he was in confession. He would then speak in Italian, and again miraculously, the person confessing who didn’t know Italian would understand Padre Pio. Just like, if you remember, both the Indians in New Mexico and Blessed Mary of Ágreda who was in Spain, could miraculously understand each other. St. Pio said that it was his guardian angel who was translating for them.

God bless you. I’ll look forward to seeing you for our next lesson.