One evening an old Cherokee told his grandson about a battle that goes on inside people. He said, "My son, the battle is between two "wolves" inside us all. One is Evil. It is anger, envy, jealousy, sorrow, regret, greed, arrogance, self-pity, guilt, resentment, inferiority, lies, false pride, superiority, and ego. The other is good. It is joy, peace, love, hope, serenity, humility, kindness, benevolence, empathy, generosity, truth, compassion and faith." The grandson thought about it for a minute and then asked his grandfather: "Which wolf wins?" The old Cherokee simply replied, "The one you feed."
As a believer in Jesus Christ you may not have a wolf inside you, but you do have an old fleshly nature which wars against your new spiritual nature. Who wins the battle? The one you feed. Romans 13:14 instructs us to put on the Lord Jesus Christ (new nature), while not making provision (feeding) for the flesh (old nature). The nature you feed the most will grow stronger and thrive, while the nature you starve will become anemic and wither. Which nature are you feeding the most? Answering this question is as simple as taking note of how you spend your time. If you spend the majority of your time feeding your flesh it stands to reason that you are going to struggle to put off the flesh and walk in the Spirit.
Romans 8:5 “For they that are after the flesh do mind the things of the flesh; but they that are after the Spirit the things of the Spirit.”
Guard against feeding your flesh by filling your mind with carnal things. Instead, fill your life (and mind) with spiritual things – reading God’s word, praying, meditating on God and the things of God, watching/listening to sermons, reading books about spiritual life, listening to Christ-centered music, fellowshipping with other believers, serving others in the name of Christ. Analyze your life. Ask yourself, is this activity feeding my flesh or my spirit?
I know it may seem impossible to only fill your life with spiritual things and activities. However, this mindset reveals a fundamental flaw in our thinking about life. All of life has spiritual implications. Your career (job), your schooling, your hobbies, your family life, your social life, your finances should all be viewed through spiritual lenses. See God in everything you do. Serve him in whatever you’re doing. If you have an activity in your life where God can’t be seen or served, then maybe that is an activity that should be mortified (Colossians 3:5).