“Watch over your heart with all diligence, for from it flow the issues of life.” Proverbs 4:23
But HOW shall the heart be kept right?
You must watch against any evil thoughts lodging in your mind. You may not be able to prevent them arising, but endeavor to drive them away as soon as you can. A flock of birds may fly over your head–but you would not let them build a nest in your hair! Little flies or insects in summer are very troublesome sometimes–but you take pains to keep them from getting into your eyes, or irritating your face and hands. In the same way, watch against every bad thought.
Remember that among the thousands of thoughts that pass through your mind in a day, there is not one hidden from God! He understands your thoughts afar off, and in His sight the thought of foolishness is sin. Therefore be watchful–do not dwell on anything that may pollute the mind. Cast away murmuring thoughts, angry thoughts, impure thoughts–and pray that God would preserve you from them. “Let the words of my mouth, and the meditation of my heart be always acceptable in Your sight, O Lord!”
But to keep away thoughts that do harm–nourish thoughts that will do you good.
“Finally, brothers . . . 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
There is a good old proverb, “Fill the sack with wheat–and there will be no room for chaff!” Fill your heart with kind thoughts, grateful thoughts, holy thoughts–and you will be safe. Let God’s thoughts which are given to us in the Bible–leaven all your thoughts. Hide in your heart the promises and precepts of His Word.
But above all, live in a spirit of prayer. Believe that God is always ready to hear you–and often go to Him for help. Draw near to God–and He will draw near to you. Nothing will keep your heart in a holy, happy frame, so much as prayer.