Read whatever you want, who's stopping you?
I simply look at it this way, if I want to truly know and understand God, why would I read a book written by fallible man, when I can read the book written by God himself?
I am not saying it is not useful to read what theologians have to say on occasion. If you come across a difficult passage of scripture that is hard to understand, I will on occasion consult a commentary. When I do so, I usually try to look at several commentaries to get different points of view. I look at the arguments and supporting scripture and then compare them to the Bible to see if they are correct.
But honestly, just my personal opinion, I have never found commentaries by theologians very helpful. I had a great pastor years ago, very knowledgeable of the scriptures. He once told me he quit reading commentaries years ago. I asked him why, and he said that the same passages that gave him difficulty also gave the theologians difficulty. They weren't any more certain of the correct interpretation than he was when he read it. So, he said he just asks God to help him understand difficult scripture.
And I have found this great advice. Oh, I know many will disagree, but I have found if you study enough, and ask God to help you understand the scriptures, he will.
Jam 1:5 If any of you lack wisdom, let him ask of God, that giveth to all men liberally, and upbraideth not; and it shall be given him.
6 But let him ask in faith, nothing wavering. For he that wavereth is like a wave of the sea driven with the wind and tossed.
7 For let not that man think that he shall receive any thing of the Lord.
8 A double minded man is unstable in all his ways.
This is a wonderful promise, but it is conditional. You have to really BELIEVE it.
I do find books on history useful. It is helpful to know and understand how people lived in ancient times, this often will help a person to better understand scripture. For instance, our pastor preached this week on Genesis chapter 15.
Gen 15:9 And he said unto him, Take me an heifer of three years old, and a she goat of three years old, and a ram of three years old, and a turtledove, and a young pigeon.
10 And he took unto him all these, and divided them in the midst, and laid each piece one against another: but the birds divided he not.
11 And when the fowls came down upon the carcases, Abram drove them away.
12 And when the sun was going down, a deep sleep fell upon Abram; and, lo, an horror of great darkness fell upon him.
Gen 15:17 And it came to pass, that, when the sun went down, and it was dark, behold a smoking furnace, and a burning lamp that passed between those pieces.
18 In the same day the LORD made a covenant with Abram, saying, Unto thy seed have I given this land, from the river of Egypt unto the great river, the river Euphrates:
19 The Kenites, and the Kenizzites, and the Kadmonites,
20 And the Hittites, and the Perizzites, and the Rephaims,
21 And the Amorites, and the Canaanites, and the Girgashites, and the Jebusites.
Our pastor explained this covenant or treaty. It had some long theological name I can't remember. But in ancient days when kings would make treaties, they would cut animals in half and separate one end of their body from the other forming an aisle. Then they would walk through the center of the animals and say, "May I be as these animals if I do not perform my oath!" Then the other party would do the same thing.
In this particular story, only God walked through the divided animals. In other words, he was going to keep his oath or promise to Abraham. But he did not require Abraham to swear to be faithful to him.
The Abrahamic Covenant is an unconditional covenant. God made promises to Abraham that required nothing of Abraham. Genesis 15:18-21 describes a part of the Abrahamic Covenant, specifically dealing with the dimensions of the land God promised to Abraham and his descendants.
Perhaps someone here knows the name of this type of covenant, I can't remember, it was a difficult name, and my pastor said it is even harder to spell!
Edit- I found it with a little looking online, it is called the Ketoctin Covenant (I think).