The Heart of It All: Foundations of Christian Theology

by Peter Amsterdam

Something that I find particularly wonderful about Jesus is that His life-transforming gift of salvation is freely given to anyone who simply asks for it with a sincere and believing heart. One’s level of understanding of Christian doctrine may be minimal, but if the heart is hungry, if it is seeking a relationship with God, then it will find it—clearly, definitely, and freely—through receiving Jesus as Savior. Salvation is simple; it’s a gift. You reach out, receive it, and it’s yours. It’s so wonderful!

While receiving salvation is simple, reaching a mature understanding of the Christian faith is another matter altogether. The Christian belief system, theology, and an understanding of the Bible all require a certain level of knowledge. It’s important to gain that knowledge, which takes both focus and study. Spiritual growth occurs through the study and application of God’s Word.

A deep knowledge of Christian doctrine is a good thing to have. And yet, it is not necessary to salvation, nor is it a guarantee of a close relationship with God. One can know and love Jesus, their Savior, without understanding all the details of Christian doctrine, because they experience Him. You can believe that Jesus is the Savior, that He is God, that He walked the earth, was crucified, died, and was buried and resurrected from the dead, simply because someone shared these basics with you, giving you enough understanding to receive Him as your Savior, thus bringing you into a personal relationship with Him.

Even if you don’t fully understand all the whys and wherefores of doctrine, you can have solid faith in God, knowing that He’s there. You speak to Him in prayer; He responds and answers you. You hear His voice, you experience His supply, His healing, His love. You have a personal connection with Him, interaction, a relationship. You know He is there, He is God, He is true, not just because of the accounts recorded for our benefit in the Bible, but because He is a reality in your life, in your personal experience.

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Part 1: The Nature and Character of God

  • Chapter 1: God’s Revelation of Himself to Humanity
  • Chapter 2: God’s Holiness, Righteousness and Graciousness
  • Chapter 3: God’s Wrath and God’s Love
  • Chapter 4: God’s Self-Existence, Eternality, and Unchangeableness
  • Chapter 5: God’s Omniscience and Omnipresence
  • Chapter 6: God’s Omnipotence and Consistency

Part 2: Jesus and the Incarnation

  • Chapter 7: Who is Jesus? The God-Man
  • Chapter 8: The Incarnation
  • Chapter 9: The Two Natures of Jesus

Part 3: The Holy Spirit

  • Chapter 10: The Holy Spirit in the Old and New Testaments
  • Chapter 11: The Holy Spirit in the Early Church and Beyond
  • Chapter 12: The Holy Spirit at Work in our Lives
  • Chapter 13: The Gifts of the Spirit

Part 4: The Trinity

  • Chapter 14: God in Three Persons
  • Chapter 15: Explaining the Trinity

Part 5: Humanity

  • Chapter 16: The Creation of Humanity
  • Chapter 17: Made in the Image and Likeness of God
  • Chapter 18: Why Humanity?

Part 6: Sin

  • Chapter 19: What is Sin?
  • Chapter 20: Humanity’s Sinful Nature

Part 7: Salvation

  • Chapter 21: God’s Plan of Salvation
  • Chapter 22: From Reconciliation to Regeneration
  • Chapter 23: Eternal Salvation
  • Chapter 24: Conclusion


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