Be cautious regarding what you think about. Memories physically modify your brain.

The Science of Memories

One thing that fascinates me about memories is that they are physical. If you can recall a thought, then it’s a memory. Medical doctors and scientists still struggle to understand how our brains can contain memories of a lifetime of visual, aural, olfactory, tactile, taste, and emotional experiences. Each memory may stand alone, like the smell of a new mowed lawn, or complexly connected, some leading to other memories and some leading to a singular memory. And as we know, memories often evoke emotions.

Each and every memory exists from some modification of our brains¹. Scientists have come up with this explanation of memories: Memories are stored as changes in the strength of synaptic connections within neural circuits, and these synaptic changes encode information that enables memory recall.

These scientific ideas about memory are fascinating, but what God has revealed about our brains far surpasses them.

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.
– Romans 12:2 ESV

Memories are the Residue of Thought

God doesn’t promise to erase our memories. The past can’t be changed. But Jesus, by the Holy Spirit, promises that for His followers who commit themselves to not being conformed [pressed into a mold] to this world, He will renew our minds.

Only recently has there been science that observed physical changes to our brains caused by the processes in our brains. We can say with confidence that memories are the residue of our mental activity – thoughts, feelings, encapsulated reactions to our five senses. No doubt, this is why the Holy Spirit had Paul write:

Finally, brothers and sisters, whatever is true, whatever is noble, whatever is right, whatever is pure, whatever is lovely, whatever is admirable—if anything is excellent or praiseworthy—think about such things. – Philippians 4:8 NIV

What About Our Soul and Spirit?

But I [Jesus] say, anyone who even looks at a woman with lust has already committed adultery with her in his heart. – Matthew 5:28 NLT

We have seen that what we think about is more than mental exercises; they have real, physical impacts on us. The soul is the essence of who we are. The topic of “soul” is a great Bible study. We will get back to our “souls” in just a moment, but first, we need to consider a person’s spirit.

Our spirit is what enables us to connect with God and communicate with Him. “For God is Spirit, so those who worship him must worship in spirit and in truth.” (John 4:24 NLT) For Christians, it is our soul and spirit that live for eternity – we also get glorified bodies. For unbelievers, their souls live for eternity in eternal punishment. Without Jesus, their spirits remain dead, separated from God.

Jesus answered, “Truly, truly, I say to you, unless one is born of water and the Spirit, he cannot enter the kingdom of God. That which is born of the flesh is flesh, and that which is born of the Spirit is spirit. – John 3:5-6 ESV

Here is what we need to remember. When God speaks to us, He energizes our minds and sometimes our senses, but what He says we retain in our souls. We may not remember exactly what we heard, we may not be able to explain it, but our souls retain the truth God spoke.

When we are alive in Christ, we are continually being transformed. Transformed means to change from one thing into another. The electricity that comes into your home goes through a transformer. The power line has a voltage of 4,000 volts or more, and the transformer changes it into the voltage in your home. If we live in Christ Jesus, our souls are transformed by the renewing of our minds – we see like Him, we think like Him, we love like Him, not with equality, but as imitators (Ephesians 5:1 NLT).

Wrapping Up

I have written more than I intended, but I hope it is helpful. Memories are the mental residue of our thoughts and actions. They physically change the structure of our minds. So, it is essential that our thoughts and actions are holy and not tainted by worldly desires.

---

Footnotes

1. Kandel, E. R., Dudai, Y., & Mayford, M. R. (2014). The molecular and systems biology of memory. Cell, 157(1), 163–186. https://doi.org/10.1016/j.cell.2014.03.001 ↩︎