Foundations of Faith Series: Understanding the Doctrine of the Trinity (+ Free Printable)

Graphic representing this truth: The Father is God, the Son is God, and the Holy Spirit is God, yet there is but one God.

Article By: Sarah Koontz

As I wrote a Bible study on the book of Ephesians a few years ago, I sought to explain the Trinity as a daisy.

The roots, stem, and flower all with different jobs/roles but the same essence.

I used one word that I should not have in my illustration, “separate.”

My pastor gently corrected me, and I’ll never forget how much respect I gained for the doctrine and also the responsibility I felt to get it right.

In fact, this experience is part of the reason I began my education at Dallas Seminary two years ago.

In order to fulfill the Great Commission—go therefore and make disciples of all nations—we must first become disciples ourselves.

A thorough understanding of God’s character and deep respect for His Inspired Word gives us the tools we need to walk intimately with Him as we invite others to do the same.

In the fall of 2020, I enrolled in Dr. Scott Horrell’s systematic theology class entitled, Trinitarianism.

Here is a brief introduction to the course written by Dr. Horrell, “Welcome to the study of our triune God. Everything in Christian theology and in the believer’s life finally comes back to who God is: the divine nature, the persons of the Father, the Son, and the Holy Spirit. The Holy Trinity is ‘the Center of Everything.’ Nothing is more astonishing, more challenging, and more potentially life-transforming than knowing God.”

Dr. Horrell defines Trinity in this manner: “The one true God eternally exists as three persons  Father, Son, and Holy Spirit  one in essence, equal in glory, and distinct in relations.”

The one true God eternally exists as three persons — Father, Son, and Holy Spirit — one in essence, equal in glory, and distinct in relations. Click to Tweet

I am excited to share much of what I learned from this class in today’s blog post.

I have also included a free PDF download about the doctrine of the Trinity. The purpose of this simple-to-read tool is to help Christians better grasp the foundational biblical concepts regarding the character and self-revelation of God.

Christian man under a starry sky contemplating the character of God

Three Reasons to Study the Doctrine of the Trinity

1. Perspective of God Grows

The God of the Bible has revealed Himself as triune—three in one! In perfect unity and oneness exist Father, Son, and Holy Spirit. As we begin to grasp the trifold nature of God, we discover that He is mightier and more magnificent than we ever imagined. As our perspective of God grows, we become so consumed by His goodness and grace that our problems pale in comparison.

2. Prayer Life is Enriched

As Christians, we are invited to enjoy fellowship with God through prayer. Each member of the Trinity participates in the process of prayer in a unique way. The Bible teaches us to pray to the Father, through Christ, by the power of the Spirit. As we develop a deeper appreciation for the distinct roles of each Person of the Godhead, we are able to pray in more strategic and powerful ways.

3. People are Reached

Many people have a faulty view of God, and the Trinity is what makes our God different from all other man-made gods. Knowledge of the triune God should not just fill our minds; it must infuse our lives with divine purpose. When we can grasp the kindness and enduring love of the Father, Son, and Spirit, we can express it through our life of worship and service. 

The God of the Bible has revealed Himself as triune—three in one! In perfect unity and oneness exist Father, Son, and Holy Spirit. Click to Tweet

Brief Statement on the Doctrine of the Trinity

The God of the Bible has always existed (Ps 90:2). He is the one and only God (Is 45:5-7), the Creator of all things (Rv 4:11), and the Sustainer of the Universe (Col 1:17). God has revealed himself as a triune Being (Gn 1:27)—one divine essence (Dt 6:4) composed of three distinct persons (Mt 28:19)—a great mystery (Jb 36:26)! He eternally exists as Father (Jn 6:27), Son (Col 1:15-17), and Holy Spirit (Acts 5:3-4). Each person of the Trinity is equal in glory (Jn 17:5) yet distinct in operations (Jn 14:16-17). Because God is triune, He has always been relational (Jn 1:18), personal (1 Cor 2:10-13), and loving (Jn 15:9). Jesus Christ is fully God (Heb 1:2-3) and fully man (Jn 1:14). One with the Father in deity (Col 2:9), He chose to take on our humanity (Phil 2:5-8), except for sin (1 Pt 2:22), in order to be a sufficient sacrifice for our sins (Heb 2:14-17). The Holy Spirit is a distinct divine person (1 Cor 2:10-13), not a mere force (Jn 14:16-17).

Christian woman's hands holding an open Bible

Sources for the Doctrine of the Trinity

Scripture: The Bible is the foundation upon which all Christian theology and doctrine must be built. The Scriptures are God’s verbal-self revelation of His character and purpose for His creation. Although the term “trinity” is not explicitly used in Scripture, God has explicitly revealed Himself as Three-in-One: Father, Son, and Holy Spirit. The Father is God, the Son is God, and the Holy Spirit is God, yet there is but one God.

History: Essential evidence for the doctrine of the Trinity is present in the eyewitness testimony from the life of Jesus Christ, as recorded in the gospel accounts. These attest to His virgin birth, pre-existence, consciousness of divine sonship, miracles, foreknowledge of death, bodily resurrection, and promise to return to earth.

Tradition: Historically, all orthodox Christian traditions affirm the doctrine of the Trinity. Our Trinitarian faith is rooted in the teaching of the Apostles, the creeds and councils of the early church, and the beloved traditions of our faith, including our baptismal formula.

Experience: The threefold Christian experience is a trustworthy source of Trinitarian doctrine. As in the New Testament, the Father, Son, and Holy Spirit continue to take an active role in believers’ lives around the world.

The Bible is the foundation upon which all Christian theology and doctrine must be built. The Scriptures are God's verbal-self revelation of His character and purpose for His creation. Click to Tweet

Development of the Doctrine of the Trinity

AD 180: Theophilus of Antioch coined the term “Triad” (Greek, τριάς) to describe “God and His Word and His Wisdom” in his book, Ad Autholycum.

AD 200: In his book, Against Praxeas, Tertullian of Carthage used the Latin term, “Trinitas,” to describe God’s nature and solidified the technical terminology that became the standard way of speaking about the Trinity moving forward.

AD 325: The definitive standard of Trinitarian faith is set forth at the Nicene (or First Ecumenical) Council. The Nicene Creed declares the consubstantiality (homoousios) of the Son with the Father. This Creed was refined at the Second Ecumenical Council in 381.

AD 451: The Chalcedonian Creed (Definitio Fidei) of the Fourth Ecumenical Council affirms that Jesus Christ possesses fully both a human nature (excepting sin) and a divine nature in a singular personal consciousness.

In the beginning was god | Doctrine of the Trinity

God the Father

“We believe in one God, the Father, the Almighty, Maker of heaven and earth, of all that is, seen and unseen.” Nicene Creed (AD 325/381)

God the Father is the Source of all things. Scripture reveals the Father’s primary roles as Creator, Ruler of the Universe, Holy Judge, Compassionate Reconciler, and the One to Whom all things will return. He is the Lord God, the Ancient of Days, the Most High God.

His personal name in covenant with His people is YHWH, meaning, “I am; to be; He is.” Throughout the Old Testament, God the Father revealed His character to Israel through His divine commands, divine intervention, and divine direction.

Jesus is the One who teaches us to call God our Father and to come before Him as adopted sons and daughters. Jesus also revealed the Father’s character and being to us throughout His life on earth. The Holy Spirit testifies to our spirit that we are God’s children.

Our Heavenly Father is loving and personal. He condescends to relate with us and has sacrificed greatly to invite us into a personal relationship with Him. He is faithful, merciful, longsuffering, and kind. He is everything our heart longs for and more.

Our Heavenly Father is loving and personal. He condescends to relate with us and has sacrificed greatly to invite us into a personal relationship with Him. Click to Tweet

Scripture References: Genesis 1:1-3 • Exodus 20:11 • Psalm 89:1; 104:31; 145:9 • 1 Kings 22:19 • Matthew 11:25 • John 6:27; 14:8-9; 15:9-12,26 • 1 Corinthians 8:6; 15:24-28; 29:11-12 • 2 Corinthians 5:18-19 • Ephesians 1:3-6; 4:6 • Hebrews 1:3 • 2 Peter 3:9-10

Photo of an actor representing Jesus Christ on the day of His crucifixion

God the Son

“We believe in one Lord Jesus Christ, the only Son of God, eternally begotten of the Father, God from God, Light from Light, true God from true God, begotten, not made…” Nicene Creed (AD 325/381)

Jesus Christ is fully God and fully man. His two natures exist, unconfused and unmingled in a singular personal consciousness. He is the eternally begotten Son of the Father and the divine Heir of all creation. He has always existed, and He has always been God.

Because Jesus is fully God and fully Man, his death on the cross has infinite value for all who profess His name. Jesus chose to empty himself and assume a human nature so that He could serve as the atoning sacrifice for the sins of humankind. He was born of a virgin, performed miracles, died for our sins, raised from the dead, ascended to heaven, and promised to return for His people. We know this because of the eyewitness testimony of Scripture and because of the work of the Holy Spirit testifying within us. Jesus is the source of our salvation and our eternal hope.

Through Him, we have access to the Father, and because of Him, we have the promise of the Holy Spirit. Because He has conquered death and sin, we have the opportunity to spend all of eternity worshiping His holy name. As Christians, we wait eagerly for His return.

Jesus Christ is fully God and fully man. His two natures exist, unconfused and unmingled in a singular personal consciousness. Click to Tweet

Scripture References: Matthew 1:23; 8:2; 9:25; 28:9,17-19 • Luke 17:20-37; 24:5-53 • John 1:1-4,14,18; 3:18; 8:58; 7:1-11; 10:30; 11:17-44 • Acts2:22-36 • 1 Corinthians 15:54-55 • Philippians 2:5-11 • Colossians 1:6,15-19; 2:9 • Hebrews 1:1-3,8 • 1 John 2:2

Graphic representing the Holy Spirit as a dove | Doctrine of the Trinity

God the Holy Spirit

“We believe in the Holy Spirit, the Lord, the giver of life, who proceeds from the Father [and the Son]. With the Father and the Son he is worshiped and glorified.” Nicene Creed (AD 325/381)

Just like the Father and the Son, the Holy Spirit is a distinct divine member of the Trinity. He is God, and He has always been God.

In Scripture, the Holy Spirit is described as our Counselor and Comforter, the Revealer of Truth, and the Spirit of Wisdom. He glorifies the Father and the Son and comes forth from the Father and the Son. He possesses intelligence and personal will. He can be grieved and blasphemed against.

By the Spirit, we are baptized, and because of the Spirit, we are sealed; He is the deposit guaranteeing our divine inheritance. The Spirit indwells us and connects us to the Father and the Son.

The Holy Spirit guides us to the truth and illuminates the path of life for us. Because of the Holy Spirit’s work on earth, we are indeed temples of the living God. May we make every effort to keep the unity of the Spirit through the bond of peace.

Just like the Father and the Son, the Holy Spirit is a distinct divine member of the Trinity. He is God, and He has always been God. Click to Tweet

Scripture References: Matthew 12:31-32; 28:19 • John 14:16-17, 26; 15:26; 16:13-15 • Acts 5:3-4; 8:29; 13:2 • Romans 8:26-27 • 1 Corinthians 2:10-13; 3:16 • Ephesians 1:13,17; 4:30 • Hebrews 9:14

Image representing the triune nature of God | Doctrine of the Trinity

Our God is Three-In-One

“Thus the Father is God, the Son is God, the Holy Spirit is God. Yet there are not three gods; there is but one God.” Athanasius Creed (AD 500)

The God of the Bible has always existed. He is the Creator of humankind and the Originator of the Universe. Yahweh God is perfect, unchanging, holy, and sovereign.

He is wholly self-sufficient and set apart from the created world, yet He chose to reveal Himself throughout salvation history. In Scripture, God reveals Himself as tri-personal.

He is One, yet He is Three. Although there is great mystery within the Trinity, much has been revealed through God’s divine self-revelation.

The Bible teaches us that God is Father, Son, and Holy Spirit. Each person of the Trinity is equal in glory, yet distinct in relations.

There is harmony and oneness within the Divine nature. The three members of the Godhead exist in loving unity and active relationship with one another. The Father loves the Son; the Son loves the Father. The Spirit delights in and glorifies the Son and the Father.

There is freedom and community in the triunity of God. Equality, distinctiveness, and self-giving love are essential qualities of the triune God. Each person of the Trinity joyfully acts in relation to the others.

There is harmony and oneness within the Divine nature. The three members of the Godhead exist in loving unity and active relationship with one another. Click to Tweet

Scripture References: Genesis 1:27; 21:33 • Exodus 3:13-14, 20:2-3 • Leviticus 22:2,32 • Numbers 23:19 • Deuteronomy 6:4 • Job 36:26 • Psalm 19:1-6; 90:2; 95:1-11 • Isaiah 9:6; 45:5-7; 46:9-10 • Matthew 28:19 • John 1:14-18; 3:16; 4:23-24; 5:26; 14:16-17; 17:5 • Acts 17:24-29 • Revelation 4:11

Free printable resource on the doctrine of the trinity

Free Printable on the Doctrine of the Trinity

The purpose of this project was to take all the information I’ve learned about the Trinity and create a tool to help Christians better grasp this important doctrine.

I hope this free resource helps you better understand the character and revelation of our triune God, and I invite you to share this printable with your friends, family, and church community.

May God be glorified and the church be edified!

Detailed Exposition of the Doctrine of the Trinity

If you would like to read my personal exposition and detailed defense of my theological views on the doctrine of the Trinity, here is a downloadable PDF version for your reference. Please note that there are nearly eight full pages of endnotes in this document including more than 102 detailed notes explaining and defending my positions.

If you have questions about the doctrine of the Trinity, I encourage you to take some time to review the references and Scriptures I’ve included in today’s blog post and in the endnotes of my defense paper. If you do not find the answers that you are seeking, I invite you to send them to our team. We will do our best to thoughtfully, respectfully, and humbly respond to your queries.

Share this Article with Friends Online!

About the Author: Sarah Koontz

About the Author: Sarah Koontz

Sarah Koontz is the founder of Living by Design Ministries, a non-profit organization that exists to deliver free Bible Studies to inboxes around the world. She is a passionate storyteller who enjoys using illustrations to communicate deep spiritual truths. Sarah and her husband Ryan live on thirteen acres in the heart of the Black Hills, SD. They have two beautiful daughters, a rowdy flock of chickens, and a house full of foster kittens. Sarah is an avid gardener, a faithful coffee drinker, lover of one-pot-dinners, an unexpected homeschooler, and a Dallas Seminary student.

Read More on the Living by Design Blog:

Stay Nourished

with Our Weekly Blog Posts & SOULfood Saturday E-mails​

By entering your email, you agree to our Terms of Service and Privacy Policy.

Scroll to Top