Tag Archives: St. Thomas Aquinas on the Trinity

Sunday Devotional: The Holy Trinity

Matthew 28:16-20

The eleven disciples went to Galilee,
to the mountain to which Jesus had ordered them.
When they all saw him, they worshiped, but they doubted.
Then Jesus approached and said to them,
“All power in heaven and on earth has been given to me.
Go, therefore, and make disciples of all nations,
baptizing them in the name of the Father,
and of the Son, and of the Holy Spirit,
teaching them to observe all that I have commanded you.
And behold, I am with you always, until the end of the age.”

Today, the universal Church celebrates the Holy Trinity — the mystery of Three Persons in One God.

That there is but one God of three Persons — the Father, Son, and the Holy Spirit — is not only found in the above passage from Matthew 28, but also in other places in Holy Scripture:

Genesis 1:26

And God said,
Let us make man in our image,
after our likeness

John 5:7

For there are three
that bear record in Heaven,
the Father, the Word, and the Holy Ghost;
and these three are one.

Matthew 3:1, 13, 16-17

And Jesus, when he was baptized,
went up straightway out of the water:
and, lo, the heavens were opened unto him,
and he saw the Spirit of God descending like a dove,
and lighting upon him:
And lo a voice from heaven, saying,
This is my beloved Son, in whom I am well pleased.

Our greatest theologians had sought in vain to plumb the mystery of the Triune Godhead — of three Persons in one God.

Some used analogies — that the Trinity is akin to the trifoliate or three-leaf  clover. But like all analogies, the clover analogy in the end doesn’t really explain or help us understand how exactly three Persons make up one God.

St. Thomas Aquinas concluded in Summa Theologica:

We cannot come to the knowledge of the Trinity by reason alone, that is, by the natural and unaided efforts of the human mind. By our natural reason, we can know that God exists; that he is the First Cause of all; that he is one, infinite, simple, immutable, etc. But that the one God subsists in three really distinct Persons is a truth that can be known only by supernatural means. That is a truth beyond the reach of human reason to know, to prove, or to disprove. We know this truth by divine revelation, and accept it by supernatural faith; we take it upon the authority of God himself.… By aid of the light of glory the soul in heaven sees God himself clearly and truly.

And so we accept our human limitation and believe, putting our trust in the words of St. Paul that we shall understand fully when we see God face to face:

1 Corinthians 13:11-12

When I was a child, I spoke like a child,
I thought like a child, I reasoned like a child;
when I became a man, I gave up childish ways.
For now we see in a mirror dimly,
but then face to face.
Now I know in part;
then I shall understand fully,
even as I have been fully understood.

May the peace and love of our Lord Jesus Christ be with you,

~E