Ephesians 5:26 English Standard Version (ESV) that he might sanctify her, having cleansed her by the washing of water with the word,
The first thing Saul did after his conversion was to be baptized. He immersed himself in water.
We have already been baptized and now our temple needs to be cleansed by immersing ourselves in the Word. Jesus cleans His house by the washing of the word.
Everyone who cleans houses has a preferred method of cleaning. It is how they see the job is best done according to their own experience. If we hire someone to clean our house it is an insult to tell that professional how to do their job.
In our case what is needed is total immersion in the Word of God. But Jesus is the Word. John said He is in his gospel. Since Jesus abides in us, He applies Himself to clean His temple.
If one is going to clean this temple, perhaps the place to start is in the attic. A place where we store things in darkness which we do not use daily. That would be the highest point, our old brain. He will begin there by taking out the cobwebs and give it a good thorough washing.
Romans 12:2 English Standard Version (ESV) Do not be conformed to this world, but be transformed by the renewal of your mind, that by testing you may discern what is the will of God, what is good and acceptable and perfect.
Ephesians 5:8-10 English Standard Version
8 for at one time you were darkness, but now you are light in the Lord. Walk as children of light 9 (for the fruit of light is found in all that is good and right and true), 10 and try to discern what is pleasing to the Lord.
We cannot discern what is good, right and true without some light shining in the dark places.