Never use a commentary. Rather depend upon God.
He it is who reveals and opens the Scriptures, if you wait upon Him. Of course you must approach with humility and allow Him to lead.
Scripture interprets Scripture so nothing beats a thorough knowledge of the Scriptures and the Holy Spirit is enabled to bring to you and unlock to you through His own word.
To assist there are two invaluable aids :
1. A concordance, as you are considering.
2. The Treasury of Scripture Knowledge - which is simply a compilation of Scripture references to almost every verse in the Bible.
You may obtain these free from www.e-sword.net with no strings attached. It is in fact the best programme by far, better than expensive ones that you can buy.
Combine that with careful reading and much pondering, consideration and of course prayer for enlightenment.
Above all dependence upon the Holy spirit and waiting upon Him is most important through careful attention to all of the Bible, not just some parts.
I repeat do not use commentaries which are men's works but obtain from God through the Bible itself. You'll not regret it.
Men's works will only give you a kind of head knowledge, a mental, intellectual knowledge which can deceive you as to your true state. It may only be their opinions. The Bible is for communion, not head knowledge and opinions. What God reveals brings a growing relationship and confidence in Him and a true heart knowledge that will become a part of you. There is nothing to be compared with that. Nothing.
It's your choice of course. A kind of quick fix by man or a true unfolding of spiritual treasure and knowledge of God Himself.
No choice really.
MEM. O how love I thy law! it is my meditation all the day.
Thou through thy commandments hast made me wiser than mine enemies: for they are ever with me.
I have more understanding than all my teachers: for thy testimonies are my meditation.
Allow me to repeat the last.
I have more understanding than all my teachers: for thy testimonies are my meditation.