In 1854, London was stricken with a devastating cholera epidemic. No one knew the cause of the disease. Panic was widespread.
Dr. John Snow, studying the deaths of 89 people in one week in the Soho district of the city, discovered that all but two of the victims drank from the Broad Street well. When asked his advice in an emergency meeting of concerned leaders, Snow suggested, "Take the handle off the Broad Street pump." It was done and the epidemic in that quarter of the city ceased.1
But removing the pump handle didn't solve the fundamental problem. Sewage was seeping into the well, poisoning it. The well must be protected from contamination to secure a safe water supply for the future.
The Bible pictures the heart as a spring or well. Proverbs 4:23 exhorts us,
"Keep2your heart with all vigilance,3for from it flow the springs4of life." (NRSV)
Guard your heart, because sewage in your heart will poison your whole life.
We must be continually on our guard against the subtle spiritual sewage that would trickle in and pollute. A hurt, an offense, can fill us with bitterness. At some points in my life I've found myself having to bail anger and resentment out of my heart several times a day so it doesn't turn to bitterness in my heart.
But other things pollute the heart, too. A hint of gossip can finish a friendship. A repeated sin can plunge us into the depression of guilt. A frantic busyness or the laziness of leisure can dull the heart with apathy toward God.
We have all met people whose spiritual lives have been sidetracked and crippled by failing to guard their hearts diligently. It could easily happen to us.
How then are we to guard our hearts? Several principles are essential.
Is Christ in your heart? Are you forcing Him to live among filth? If will allow Him, He will help you cleanse your heart. As we live as Jesus' disciples, we will guard our hearts with all diligence from anything that will prevent them from being places fit for the King.
1. More about thischolera epidemicandDr. John Snow, the father of epidemiology, can be found on Wikipedia.2. "Guard" (NIV), "keep" (NRSV, KJV) isnāṣar, "watch, guard, keep." (Walter C. Kaiser, TWOT #1407).3. "Above all else" (NIV), "diligence" (KJV), "vigilance" (NRSV) ismishmār, "place of confinement, jail, prison," late, "guard, watch, observance." The basic idea of the rootshāmaris "to exercise great care over", a synonym ofnāṣarused in the same phrase. (BDB 103).4. "Wellspring" (NIV), "springs" (NRSV), "issues" (KJV) istoṣāʾot, "exits" (from a city), here "starting-point" (of life) (Holladay,Lexicon, p. 388), fromyāṣāʾ, "go out, come out, go forth" (Paul R. Gilchrist, TWOT #893).