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Theology & Doctrine

Understanding the Core Truths of the Christian Faith

Theology is the study of God and His ways, drawn from the truth He has revealed in Scripture. Doctrine is the organized teaching of those truths. Together, they form the foundation for what Christians believe and how we live.

Sound theology protects us from error, strengthens our confidence in God, and shapes our worship, mission, and daily lives. This page explores essential Christian doctrines, explains their biblical basis, and shows why they matter today.

1. Salvation (Soteriology)

The Problem

All have sinned and fall short of God’s glory (Romans 3:23). Sin separates us from Him and brings spiritual death.

God’s Solution

Salvation is entirely God’s work — a gift of grace through faith in Jesus Christ (Ephesians 2:8–9).

Key Aspects

  • Justification: God declares a sinner righteous on the basis of Christ’s work (Romans 5:1).

  • Regeneration: The new birth by the Holy Spirit (John 3:3–5).

  • Adoption: Believers are brought into God’s family (Romans 8:15–17).

  • Sanctification: Ongoing growth in holiness by the Spirit’s power (1 Thessalonians 4:3).

  • Glorification: Final transformation into Christ’s likeness in eternity (Romans 8:30).

2. Grace

Grace is God’s unearned favor — His kindness toward those who deserve judgment.

  • Common Grace: Blessings God gives to all people (Matthew 5:45).

  • Saving Grace: The specific grace that brings a sinner to salvation.

  • Sustaining Grace: The daily strength God provides to His children.

3. Justification by Faith

One of the central truths of the Reformation:

  • By Grace Alone: Salvation is not earned by works.

  • Through Faith Alone: Trust in Christ’s finished work, not in self.

  • In Christ Alone: He is the only mediator between God and man (1 Timothy 2:5).

James 2:26 reminds us: “Faith without works is dead.” Works are the evidence of genuine faith, not the means of earning salvation.

4. Sanctification

The Spirit works in believers to make them more like Jesus:

  • Definitive Sanctification: At conversion, believers are set apart as holy in God’s sight.

  • Progressive Sanctification: Lifelong growth in obedience and character.

  • Means of Grace: Prayer, Scripture, fellowship, sacraments, service.

5. The Person of Christ (Christology)

Fully God, Fully Man

The Bible teaches that Jesus is both divine (John 1:1) and human (John 1:14).

Work of Christ

  • Prophet: Reveals God’s truth.

  • Priest: Offers Himself as the perfect sacrifice for sin.

  • King: Rules and will return to reign fully.

6. The Holy Spirit (Pneumatology)

See the Holy Spirit page for a full treatment, but in doctrine:

  • He proceeds from the Father (and the Son).

  • He indwells believers, seals them, and equips them with gifts.

  • He produces the fruit of the Spirit as evidence of His presence.

7. Covenant and Law

God relates to humanity through covenants — solemn commitments:

  • Old Covenant: Given to Israel, centered on the Law of Moses.

  • New Covenant: Established in Christ’s blood (Luke 22:20), offering forgiveness and transformation through the Spirit.

The moral law reveals God’s character and continues to guide Christian living.

8. Sacraments / Ordinances

Jesus gave two primary practices for the Church:

  • Baptism: Sign of entry into the covenant community.

  • The Lord’s Supper: Ongoing remembrance of Christ’s sacrifice.

Different traditions may use the term “sacraments” or “ordinances,” but both view these as commands given by Christ for the Church’s good.

9. Eschatology (End Times)

While Christians may differ on the details, core truths include:

  • Jesus will return visibly and gloriously.

  • There will be a resurrection of the dead.

  • God will judge all people with perfect justice.

  • Believers will enjoy eternal life in the new heavens and new earth.

10. Guarding Sound Doctrine

Why It Matters

  • Protects the Church from false teaching (Titus 1:9).

  • Unites believers in truth (Ephesians 4:13–15).

  • Fuels worship and mission.

How to Guard It

  • Know the Scriptures deeply.

  • Test all teaching against the Bible (Acts 17:11).

  • Stay rooted in a healthy local church.

11. How Doctrine Shapes Life

Doctrine is not an abstract mental exercise — it’s truth meant to be lived:

  • Knowing God’s holiness leads to humble worship.

  • Understanding grace fosters gratitude and generosity.

  • Believing in Christ’s return motivates holiness and mission.

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