"Above all else, guard your heart, for everything you do flows from it." – Proverbs 4:23 (NIV)

Everyone who's ever tried to guard their heart against all sorts of impurities and wrongs knows that it's not an easy thing to do. It requires much effort, demands much vigilance, and needs a strong commitment to keep guarding it at all times.

But why does the heart require much effort to guard? Why would a seemingly simple thing to do demand much attention? Let's look at two possible reasons: inner conflict and outside interference.

Inner conflict

The heart is called the "spring" from where all of life's issues come from (see Proverbs 4:23 NKJV). All of the issues of life that we face, whether negative ones such as lust, greed, and hatred or even positive ones such as love, care, and affection, spring from it. We can imagine the heart to be where all of these thoughts are formed.

The problem is, man's heart is not pure and holy. Because of sin all men fall short of the glory of God, each of us turning to our own ways whether wicked or not (see Romans 3:23; Isaiah 53:6). Our hearts aren't the loveliest of all things.

Jeremiah 17:9 tells us one of the most obvious reasons why guarding the heart is such a challenge:

"The heart is more deceitful than all things and desperately wicked; who can understand it?" (MEV)

True enough, the heart is indeed deceitful. If you find that unbelievable then just consider the lies many of us believe. Before we came to Christ, many (if not all) of us believed in all sorts of things. Sadly, there are still some Christians who believe things that are contrary to what is written in the Bible.

The Lord Jesus said purity is a matter of the heart. He said in Mark 7:21-23,

"For from within, out of the heart of men, proceed evil thoughts, adultery, fornication, murder, theft, covetousness, wickedness, deceit, licentiousness, an evil eye, blasphemy, pride and foolishness. All these evil things come from within and defile a man.""

The unredeemed, unrenewed heart that isn't washed and purified by the washing of God's Word will remain a deceitful, impure heart.

"How shall a young man keep his way pure? By keeping it according to Your word." (Psalm 119:9)

Outside interference

Now that we've established that the heart will remain deceitful without the Word of God, Christians who adhere to the Word of God and do what the Psalmist said in Psalm 119:9 still face outside pressures in the fight to guard the heart.

For starters, just consider what the Lord Jesus said about what we see or look at:

"The light of the body is the eye. Therefore, if your eye is clear, your whole body will be full of light. But if your eye is unclear, your whole body will be full of darkness. Therefore, if the light that is in you is darkness, how great is that darkness!" (Matthew 6:23-24)

Still, we cannot blame outside factors for the challenge we face in guarding our hearts. It still boils down to what we choose for ourselves: we can choose to be impure even in the midst of seemingly innocent situations (see Matthew 5:21-22, 27-30), or choose to meditate on what is true, pure, right and God-pleasing even in the midst of unfavorable conditions (see Philippians 4:8).

In conclusion

Friends, the heart isn't something we should take lightly. We are commanded to guard it "with all diligence," and that counsel doesn't come without basis. The heart is a very fragile thing, something we must give much care to defend against sinfulness.  But take heart because, with God's help, it is possible.  We have spiritual armor and spiritual weapons at our disposal if we spend regular, in fact daily, time in God's Word and in prayer.  Friend, this battle is spiritual so it will take spiritual power to defeat it; do not cut off your supply by neglecting the basics of the faith.

I leave you with this exhortation: Let's adhere to the Word of God, do our best to let it fill our hearts and minds, and obey it with all that we have.

"Blessed are those whose way is blameless, who walk in the law of the Lord. Blessed are those who keep His testimonies, and who seek Him with all their heart. They also do no wrong; they walk in His ways... Your word I have hidden in my heart, that I might not sin against You." (Psalm 119:1-3, 11)