You should study theology. Theology comes from two Greek words “theos” (God) and “logos” (word).
Theology then is the study of God. A systematic theology assumes the canon of Scripture is closed and there is no more inspired revelation from God, so we have the full and complete revelation of God. We can take the Bible and study all of what God has said on a related subject and in a logical and precise manner, have an understanding of a particular issue. The inspired Word is authoritative, sufficient, and consistent, so there will be no contradictions on any subject.
Theology isn’t just for pastors. In fact, everyone should be a theologian. If you don’t study theology, that simply means you just aren’t a very good theologian. Everyone has opinions about God and Christians should derive what they think about God and religion from the Bible. The Christian would be well served to dedicate themselves to the study of systematic theology. There are many books put out by Christian publishers and so much of it is drivel. One man said the most dangerous place a Christian can go in this earth is a modern Christian bookstore. False doctrine sells, unfortunately. Instead of a powder-puff devotionals that gives you milk, at best, and poison at worst, try reading a systematic theology for your devotional time. Just a few pages a day will give you plenty to ponder, lots to learn, and meditating on deep truth will give you a deep awe of your God.
There are many fine works of systematic theology published, but I would recommend that you find a good trusted author from the past. Dead men can’t change their mind on you down the road. Also, you are choosing a work that has stood the test of time and since they have been around for a while, you can already know where they may be wrong on a point or two. Remember, the only inspired book is the Bible, and all books need to be read with discernment. Some are easier to read than others. T.P. Simmons, for example, wrote a very good and accessible systematic theology that would be a terrific place to start. James Boyce’s Systematic Theology and John Gill’s Body of Divinity are both excellent works, but a little more advanced. Get all three and make that a long term project. Reading just a couple pages a day, you can chip away at a big book. Imagine, knowing more about the God who saved you. Think about knowing more about Jesus and getting a deeper understanding of the covenant of redemption. Don’t think theology is cold and dry. Will learning more about your God and what He has done for you make you love Him less or more? Will learning more about his grace make you more or less appreciative of His divine favor? Dig deep and learn. After all, a “disciple” is a student. Read your Bible first, and when you are done, try some theology.