Simply Explained

The Holy Trinity is one of the central mysteries of the Christian faith. It is the belief that there is one God in three Persons: God the Father, God the Son (Jesus Christ), and God the Holy Spirit. The Trinity can be hard to understand, even for adults – and that’s okay! Christians don’t believe in three gods, but in one God who is a communion of three Persons. It’s a bit mysterious, but we’ll break it down in simple terms (using some examples, like St. Patrick’s shamrock) to help explain it.

What does “Trinity” mean?

The word Trinity comes from “tri-” (meaning three) and “unity” (meaning one). So it basically means “three-in-one.” When we say God is a Trinity, we do not mean there are three separate gods. In fact, Christianity is monotheistic – a big word meaning we believe in one God. However, within the one God there are three divine Persons. They are not three parts of God; rather, each of the Persons is fully God. The Father, Son, and Holy Spirit are distinct from each other (the Father is not the Son, and the Son is not the Holy Spirit), but they are perfectly united in one God. As the Church plainly teaches: “We do not confess three Gods, but one God in three persons”. In short, the Trinity is the mystery of one God in three Persons. It’s a unique concept – nothing else is exactly like it!

Sometimes people ask, “Is the Trinity in the Bible?” The actual word “Trinity” isn’t in the Bible (it’s a term the early Church came up with to describe this truth), but the reality of the Trinity is definitely found in Scripture. For example, Jesus commands His disciples to baptize people “in the name of the Father and of the Son and of the Holy Spirit” – putting the three on the same divine level. Jesus often speaks about His Father, and about sending the Holy Spirit. At Jesus’ own baptism, all three Persons of the Trinity are revealed: the Father’s voice speaks from heaven, the Son (Jesus) is being baptized in the Jordan, and the Holy Spirit appears in the form of a dove. These and other passages show that the Father is God, the Son (Jesus) is God, and the Holy Spirit is God – together the one true God.

How can God be three-in-one? (Understanding the mystery)

The Trinity is a mystery, meaning our human minds can’t fully comprehend it – and that’s okay, because God is greater than we are. But we can understand it a little. One way to think about it is that God is love. For love to exist, there needs to be a lover, a beloved, and the love they share. Some have used this as an analogy: God the Father loves the Son, the Son loves the Father, and the Holy Spirit is the love flowing between them – yet it’s all one perfect love. Another way to imagine it is that our one God is like a “family” of three Persons who share the same divine nature in an eternal relationship of love.

Over time, people have tried different examples to explain the Trinity. No analogy is perfect, but they can help. You may have heard that the Trinity is like water, which can exist as ice, liquid, and steam – three forms, but all water. Or like the sun, which has the star itself, its light, and its heat – three “aspects” but one sun. Or like a triangle with three corners but one shape. Each comparison has its limits (for instance, water can’t be all three states at once – but God is always Father, Son, and Spirit at the same time). Still, these examples give us a tiny insight into how something can be three and one at once. The Trinity isn’t exactly like anything in nature, but these comparisons help us grasp how unity and diversity coexist in God.

St. Patrick’s shamrock explanation

One of the most famous illustrations of the Trinity is attributed to St. Patrick, a missionary who taught the Irish people about Christianity in the 5th century. According to legend, St. Patrick used a common shamrock (a three-leaf clover) to explain the Trinity. The shamrock has three little leaves, but it’s still one clover. In a similar way, God is three Persons, but one God. The Father, Son, and Holy Spirit are distinct (like each leaf of the clover) but they are one divine Being (like the clover is one plant). This simple example helped people understand how God can be “three-in-one.”

Of course, the shamrock is just an analogy – God is far greater than any plant! No analogy can capture God completely. But St. Patrick’s shamrock idea is a handy way to remember that the one God has a triune (three-in-one) nature. Even today, the shamrock is often used as a symbol of the Trinity in churches and art, thanks to this famous story.