Take no part in the unfruitful works of darkness, but instead expose them. For it is shameful even to speak of the things that they do in secret. But when anything is exposed by the light, it becomes visible, for anything that becomes visible is light.
Therefore it says, ?Awake, O sleeper, and arise from the dead, and Christ will shine on you.?

It is so wonderful to see how the Holy Spirit makes things clear for us. You could read the Bible a thousand times and yet, every single time, you will read something and the Holy Spirit will give you wisdom in understanding the text in its totality. I do not know if it is just me, but sometimes I do feel so uneducated, because things that might seem simple to others have a huge impact on me. Just like this section in Ephesians.
The King James version says: "and have no fellowship with the unfrutiful works of darkness, but rather reprove them.
The NLV says: "take no part in the unfruitful works of darkness, but instead expose them.
Sometimes, you have to read various translations to really see the deeper meaning. For me this is what I believe it is saying and I am going to use an example to explain it:
Lets say you have thoughts of lust. Do not entertain (fellowship, take no part) it because it is not from God (the light), it is from Evil (the darkness), rather bring it to God (the light) by admitting it and praying about it all the time. That way, you are exposing the darkness to the light and no darkness can remove the light.
When your sin is exposed, you have won victory over it and the Holy Spirit will guide you away from it, making you stronger.