"...THINK ON THESE THINGS..."

Protect Your Mind; It's Not An Open Field

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There are people whose minds are like an open field that anyone (or animal, for that matter) can go through and drop unwanted seed. When you leave your mind open this way, any worthless seed can be thrown in it and WII grow. your spirit that the Bible describes as a field, not your mind. And because your spirit is only accessible through your mind—which is the door to your spirit—nothing can get in there that you don't first allow in your mind.

Tha's why the Lord instructs us: "Keep thy heart
with all diligence; for out of it are the issues of life" (Proverbs 4:23).
The word, "keep," used in this scripture is the same used in Genesis 2:1 5: "And the Lord God took the man and put him into the garden of Eden to dress it and to keep it" It doesn't suggest putting or separating the garden away to somewhere safe. It actually implies taking care of it in a protective way and ensuring its security against any external aggressor.

The Good News Bible translation puts it clearer. It says, "...the LORD God placed the man in the Garden of Eden to cultivate it and guard it" The word "guard" has a military connotation, which suggests protecting from attack or maintaining in safety from danger.

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You'd agree that if there's no enemy or adversary, there wouldn't be any need to guard something that belongs to you against an attacker. Truth is, there's an adversary, and that why the Lord instructs you to keep—or guard—your heart with all diligence.
I love James Moffat's delivery of Proverbs 4:23-2
He says in his translation, "Guard above all things, guard your inner self so you can live and prosper. Bar out all thoughts of evil and banish wayward words."
Have you ever heard someone say, "l was barred from joining the team"? It means he was prevented, kept out, blocked, or disallowed from joining the team. That's how the Bible tells you to guard your heart, by barring (disallowing, keeping out) all thoughts that are not consistent with God's Word.
Now, this doesn't sound like the evil thoughts are originating from you, does it? What it simply shows is that there's a devil out there trying to send the wrong thoughts into your heart (through your mind). So you're admonished to bar his evil thoughts and banish his wayward words.
If someone says something to you that challenges God's Word, bar it from your mind! Don't try to accommodate it or reason it out. The Bible says to guard your heart with all diligence, so you must recognise that God is not going to guard your heart for you. The responsibility is yours. But the good news is that you're not helpless as to what to do. You've been equipped with "the whole armour of God" (Ephesians 6:1 1 and what you need to do is put it on and never take it off! With your armour in place, you'll be able to bar every evil thought or idea against God's Word that tries to assault your mind (We'll be looking at this in greater detail in chapter seven).

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God's Yardstick For Measuring Good Thoughts

God didn't just instruct us to mount guard at the door of our hearts and disallow anything from passing through that shouldn't; He also shows us exactly how to place that guard over our minds— by choosing the thoughts we allow passage. In other words,He didn't just tell us to renew our minds without showing us how. He told us the files to delete from our minds and the new ones to download and replace them with.

"Finally, brethren, whatsoever things are TRUE, whatsoever things are HONEST, whatsoever things are JUST, whatsoever things are PURE, whatsoever things are LOVELY, whatsoever things are of GOOD REPORT; if there be any VIRTUE, and ifthere be any PRAISE, think on these things" (Philippians 4:8).

How remarkable this is! It immediately shows us God's yardstick for measuring good thoughts. It says whatever things are consistent with truth [God's Word], excellent, lovely, of good report, and praiseworthy, focus your mind on these. In other words, let these thoughts occupy your mind and control your thinking process.