Hebrews 5:14 says that Mature Christians are people who, by constant practice, have trained their ability to discern between good and evil. What exactly does this mean? Mature Christians are the moral police? Are we back to rule keeping? On a practical level what does this look like?
I want to try and answer this question by looking at another passage of scripture. In the book of Philippians Paul tells them something that he has been praying for them. This is what he says in Philippians 1:9-11. "And it is my prayer that your LOVE WOULD ABOUND more and more, with knowledge and all discernment, so what you may be able to approve of what is excellent and so be pure and blameless for the day of Christ, filled with the fruit of righteousness that comes through Jesus Christ to the glory and praise of God!
When the writer of Hebrews said that mature Christians have their "powers of discernment" trained I think he had something far greater that Christian rule keeping in mind. In this culture of ours we feel a constant need to be careful about not sounding judgmental or critical and just let everybody live their lives. As a result we want to run far away from anything that sounds too much like religiosity or law-keeping. But Christian maturity does involve a growth in holiness, discerning and choosing to live in what is excellent.
So, who decides what is excellent? Isn't in the word of God? That's what is being taught in Hebrews 4 and 5. The word of God is like milk to a baby. As you drink it and, by constant practice apply it to your life, you grow in your ability to discern what is excellent in your daily living. What will I watch or not watch? What will I say or not say? How will I treat my wife? How will we spend our money? By what principles will I lead my business? All these are answered by the scriptures and the scriptures will in fact lead us to what is excellent and as a result our lives will be found to be pure and blameless and filled with the fruit of righteousness that brings glory and praise to God. This is the mature Christian's greatest desire: God being honored in his or her life.
What motivates this kind of life? LOVE It is my prayer that your LOVE will abound more and more. We begin with the steadfast love of God for us first. That's why Paul prayed for the Ephesians that they would have the strength to know the depth, width, height, and breadth of God's love for them. John said we love because He first loved us. Our love abounds through knowledge and all discernment. As we grow in our knowledge of who God is we will desire to love Him in return. He will become valuable to us. Loving God and loving others will become a driving force in our lives. When Love for God and love for others is growing in our lives it will naturally lead us to ask the question, "What is the excellent, loving, God-honoring thing to do in this situation?"
So, are we the moral police? No! Are we passionately pursuing holiness (to be Christ-like) and excellent and good moral choices for our lives in order to bring glory and praise to our Father out of heart of love? YES! This means we will first pursue this for our own lives and families. We can then boldly and humbly hold these virtues up to others as a means of showing love to God and love to others and display what God is like to the world.