The study of God is usually referred to as Theology Proper to distinguish it from the study of Theology in general, which covers the many branches of study. God has revealed Himself to us not only through creation, but also in His Word.
God is Spirit (John 4:24), an infinite, eternal Being (Psalm 90:2). How can we ever hope to know Him? As finite, mortal creatures we will never be able to fully know or understand God. But He has willingly revealed Himself to us through His Word, that we might know Him and have a relationship with Him.
The study of God typically involves learning His attributes. These are often divided into what is called incommunicable and communicable attributes. Incommunicable attributes are those attributes that we don’t share with God. Having been created in God’s image, we do share to a degree some of His attributes that are referred to as communicable attributes. An example of an incommunicable attribute of God would be His Self-Existence (called Aseity). God’s Aseity means that He is not dependent on anyone or anything for His existence. In contrast, as created beings, we are dependent on God for our existence. An example of a communicable attribute of God is His love. Though we are not able to love in the same fullness as God does, we do have the capability of love to a degree.
God’s sovereignty and power can be seen in Scripture as early as Genesis 1 as the story of God creating the world is told. The repeated phrases “And God said…” with the resulting “And it was so” show that what God decrees happens. This is also portrayed in the book of Exodus as God releases His judgment on Pharaoh and the Egyptians through a series of devastating plagues. Yet we are never to emphasize one of God’s attributes over and above the others. While God is powerful, He is also loving. While He is holy, He is also merciful. When we emphasize God’s love over His wrath, we are not giving an accurate picture of Who God is. All of His attributes make up Who He is.
Part of the study of God involves talking about the Trinity. While this word is not used in the Bible, the doctrine is clear throughout Scripture as God is revealed as one God in three persons: the Father, the Son, and the Holy Spirit. This is not an easy doctrine to explain or understand. Yet it is crucial to knowing God. Luke 3 tells us of Jesus’s baptism and is one of the passages that displays the Trinity as the Father speaks from heaven as Jesus is baptized and the Holy Spirit descends on Him. 2 Corinthians 13:14 also references the Trinity as Paul writes, “The grace of the Lord Jesus Christ and the love of God and the fellowship of the Holy Spirit be with you all.” (ESV)
While Theology Proper refers to the study of God in general, the branches of Christology and Pneumatology dive further into the study of Jesus Christ and the Holy Spirit. Yet all of theology works together in helping us to understand who God is and all that He has done for us. And we discover all this in God’s written Word, the Bible.
John 20:21 (ESV): “but these are written so that you may believe that Jesus is the Christ, the Son of God, and that by believing you may have life in his name.”
Books on Theology Proper:
Knowing God by J.I. Packer
The Attributes of God by A.W. Pink