So let us stop going over the basic teachings about Christ again and again. Let us go on instead and become mature in our understanding. Surely we don't need to start again with the fundamental importance of repenting from evil deeds and placing our faith in God. You don't need further instruction about baptisms, the laying on of hands, the resurrection of the dead, and eternal judgment. And so, God willing, we will move forward to further understanding. - Hebrews 6:1-3 NLT
There is a lack of basic theology teaching in our churches today. According to a recent Barna study, less than one in five practicing Christians have a biblical worldview. A 2015 Lifeway Research survey found almost 1 in 5 churchgoers say they never read the Bible, which is the same number who read it every day. From the same survey, 1 in 5 evangelical Christians believe there are many ways to get to heaven. 59% of evangelicals believe the Holy Spirit is a force and not a personal being. Americans, including many Christians, hold unbiblical views on hell, sin, salvation, Jesus, humanity, and the Bible itself. Thankfully, 90 percent of churchgoers "desire to please and honor Jesus in all I do." , but they are not learning how to do just that.
Clearly the teaching of sound theology is sorely needed in our churches today.
Theology is the study of the nature of God and religious belief. It is simply an attempt to understand God as He is revealed in the Bible. Ultimately theology asks the question, what do you believe and why? In a sense, everyone is a theologian with a theology because everyone has some kind of belief about God even if that is a belief in no God at all.
What is your theology? Do you know what verses support your belief, or are you relying solely on what your pastor or teacher told you?
A basic understanding of theology is essential to the Christian walk. We cannot be saved without understanding at least a small amount of what the Bible says about God. We cannot grow and mature in our faith without increasing our knowledge of God and His Word. We cannot resist useless doctrinal fads and false teachers without a knowledge of the truth of God’s word. If we are not well grounded with a broad base of biblical teaching we will be susceptible to every wind of doctrine. We need to be consistent throughout the whole range of biblical doctrine so that we do not contradict ourselves in what we believe. We need to uncover and organize the truth contained in Scripture. It is not always readily available in the form the Bible chooses to present it.
Before you Gentiles knew God, you were slaves to so-called gods that do not even exist. So now that you know God (or should I say, now that God knows you), why do you want to go back again and become slaves once more to the weak and useless spiritual principles of this world? - Galatians 4:8-9 NLT
The difference between believers and unbelievers is to know God and trust in His promises, aka our theology.
So we have not stopped praying for you since we first heard about you. We ask God to give you complete knowledge of his will and to give you spiritual wisdom and understanding. Then the way you live will always honor and please the Lord, and your lives will produce every kind of good fruit. All the while, you will grow as you learn to know God better and better. - Colossians 1:9-10 NLT
To grow in the Christian faith is to expand our theology, to increase our knowledge of God through His word and apply that knowledge to our lives.
This will continue until we all come to such unity in our faith and knowledge of God's Son that we will be mature in the Lord, measuring up to the full and complete standard of Christ. Then we will no longer be immature like children. We won't be tossed and blown about by every wind of new teaching. We will not be influenced when people try to trick us with lies so clever they sound like the truth. - Ephesians 4:13-14 NLT
A solid theological foundation is essential to discernment. When they train counterfeit investigators, they don’t show them the fake money, not at first. First they teach them everything there is to know about the real thing and that knowledge reveals the imposters. When you know the truth of God’s word ferreting out the useless fads and false teachers becomes easy.
Christianity Today.com: The Epidemic of Bible Illiteracy in Our Churches