Day Two: Foundational Doctrines

Today, we are going to talk about three foundational truths of the Christian faith. These are the core of the gospel and what we believe as Christians. If we understand these three things, we begin to understand who God is, how He relates to us, and what He has done for us.

1) The Trinity (Who God Is)

The word itself, “Trinity,” is not found in the Bible, but the idea is clearly taught throughout Scripture. The Trinity means that there is one God who exists in three Persons:

• God the Father

• God the Son (Jesus)

• God the Holy Spirit

This does not mean there are three gods. There is only one God—but He exists in three distinct Persons who are all fully God.

Each Person of the Trinity is fully God, not just a part of God. They share the same nature, the same power, and the same purpose. At the same time, they relate to one another in different ways.

We can see the Trinity in the Bible in moments like Jesus’ baptism, where:

• Jesus is being baptized

• The Holy Spirit comes down like a dove

• The Father speaks from heaven

  Matthew 3:16-17

  “As soon as Jesus was baptized, he went up out of the water. At that moment, heaven was opened, and he saw the Spirit of God descending like a dove and alighting on him. And a voice from heaven said, “This is my Son, whom I love; with him I am well pleased.”

All three are present at the same time, showing they are distinct, yet one.

This can be hard to understand, and that’s okay. We are going to dive into this deeper in the weeks to come! What matters is holding onto these truths:

• There is one God, not three

• The Father, Son, and Holy Spirit are each fully God

• They are distinct Persons, but perfectly united in love and purpose

2) The Bible (How God Speaks to Us)

The Bible is God’s Word and the primary way He communicates with us. Through it, we learn who God is, how much He loves us, and how we are meant to live.

The Bible is made up of 66 books, written by about 40 different authors over a period of around 1,500 years. These authors came from very different backgrounds—some were kings, others were fishermen, shepherds, or teachers. Yet despite all these differences, the Bible tells one consistent story. This is because it ultimately has one true Author—God.

The Bible describes itself as “God-breathed,” meaning God guided each writer to communicate exactly what He wanted. Because of this, Christians believe the Bible is trustworthy, true, and relevant for our lives today.

2 Timothy 3:16

“All Scripture is God-breathed and is useful for teaching, rebuking, correcting and training in righteousness…”

The Bible is divided into two main parts:

• Old Testament – tells the story of God’s relationship with His people and points forward to the coming of a Savior

• New Testament – tells the story of Jesus, His life, death, and resurrection, and how we can have a relationship with God through Him

Even though it’s made up of many books, the entire Bible points to one central person: Jesus.

• The Old Testament prepares the way for Him and includes promises about His coming

• The New Testament reveals who He is and what He has done for us

Jesus is more than just a good teacher or historical figure—He is God in human form. When we look at Jesus, we see what God is like: loving, patient, just, and full of grace.

Because of this, the Bible is not just a book to read—it’s a guide for life. It helps us understand truth, grow in our faith, and build a real relationship with God.

3) The Gospel (The Good News)

The word “gospel” means good news. But to really understand why it’s good news, we first have to understand the problem—this is what we talked about and began to unpack during the last session.

The Bible teaches that everyone has sinned. This means we have all fallen short of God’s perfect standard—through our thoughts, actions, and choices. Because God is holy and perfect, sin separates us from Him. The result of that separation is spiritual death, meaning we are cut off from the life and relationship God created us for.

In the Old Testament, God gave His people a system of sacrifices. Animals were offered as a way to temporarily cover sin. But these sacrifices were never meant to be the final solution—they were pointing forward to something greater.

That’s where Jesus comes in.

• Jesus lived a perfect, sinless life

• He died on the cross in our place

• He took the punishment for our sin

• He rose again, defeating sin and death

Jesus became the final and perfect sacrifice. He did what we could never do for ourselves.

Because of this, anyone who believes in Him—who trusts in what He has done—can be forgiven, restored, and have a real relationship with God.

So the good news is this:
We were separated from God, but through Jesus, a way has been made for us to come back to Him.

That is the gospel.

Why Sharing the Gospel Matters

The gospel is not just good news for us—it’s good news for everyone.

Jesus calls us to share this message with others so they can also experience forgiveness, hope, and a relationship with God. Many people are searching for meaning, healing, and peace, and the gospel speaks directly to those needs.

Sharing the gospel doesn’t mean having all the answers; it simply means:

• Telling others what Jesus has done

• Sharing your story and what God has done in your life

• Showing love, kindness, and truth

When we share the gospel, we are offering others the same hope that has been given to us.