So, you’re in a battle. Why do you need to be strengthened? Because if you’re not strengthened inside by the blessed Holy Spirit of God, you’re never going to make it.
Now about this matter of a mystery, it doesn’t represent something you cannot know. When the Bible uses the word mystery, it’s something that you can’t know by yourself but which God wants to open up to you.
So if you want access into the very presence of God, number one, you have to want to; number two, you have to ask God for it through the Lord Jesus; number three, you have to go to the place where God speaks to you, and that’s in His word.