God wants you to grow up.

"God wants us to grow up, to know the whole truth and tell it in love - like Christ in everything" (Ephesians 4:15 The Message).

"We are not meant to remain as children ...." (Ephesians 4:14 Phillips).

Your heavenly Father’s goal is for you to mature and develop the characteristics of Jesus Christ, living a life of love and humble service.  Sadly, millions of Christians grow older but never grow up.  They are stuck in perpetual spiritual infancy, remaining in diapers and booties. The reason is because they never intended to grow. Spiritual growth is not automatic. It takes an intentional commitment. You must want to grow, decide to grow, make an effort to grow, and persist in growing. Discipleship - the process of becoming like Christ - always begins with a decision.

"As Jesus passed on from there, he saw a man called Matthew sitting at the tax booth, and he said to him, 'Follow me.' And he rose and followed him" (Matthew 9:9 ESV).

When the first disciples chose to follow Jesus, they didn’t understand all the implications of their decision. They simply responded to Jesus’ invitation. That’s all you need to get started: decide to become a disciple. Nothing shapes your life more than the commitments you choose to make. Your commitments can develop you or they can destroy you, but either way, they will define you. Tell me what you are committed to, and I’ll tell you what you’ll be in 20 years. We become whatever we are committed to. It is at this point of commitment that most people miss God’s purpose for their lives.  Many are afraid to commit to anything and just drift through life. Others make half-hearted commitments to competing values, which leads to frustration and mediocrity. Others make a full commitment to worldly goals, such as becoming wealthy or famous, and end up disappointed and bitter. Every choice has eternal consequences, so you’d better choose wisely.

"Since everything around us is going to melt away, what holy, godly lives you should be living!" (2 Peter 3:11 NLT).

Christlikeness comes from making Christlike commitments. You must commit to living the rest of your life for the five purposes God made. Jesus summarized these purposes in the Great Commandment and the Great Commission.

A great commitment to the Great Commandment and the Great Commission will make you a great Christian.

Once you decide to get serious about becoming like Christ, you must begin to act in new ways. You’ll need to let go of some old routines, develop some new habits, and intentionally change the way you think.

"Continue to work out your salvation with fear and trembling, for it is God who works in you to will and to act in order to fulfill his good purpose" (Philippians 2:12 NIV).

This verse shows the two parts of spiritual growth: "work out" and "work in."  The "work out" is your responsibility and the "work in" is God’s role.  Spiritual growth is a collaborative effort between you and the Holy Spirit. God’s Spirit works with us, not just in us. This verse, written to believers, is not about how to be saved, but how to grow. It does not say "work for" your salvation, because you can’t add anything to what Jesus already did! During a physical workout, you exercise to develop your body, not to get a body. When you "work out" a puzzle, you already have all the pieces - your task is to put it together. Farmers work the land, not to get land, but to develop what they already have. God has given you a new life; now you are responsible to develop it "with fear and trembling." That is to take your spiritual growth seriously, because it will determine your role in eternity. When people are casual about their growth in Christlikeness, it shows they don’t understand the implications. To change your life, you must change the way you think. Behind everything you do is a thought. Every behavior is motivated by a belief, and every action is prompted by an attitude. God revealed this thousands of years before psychologists understood it:

"Be careful how you think; your life is shaped by your thoughts" (Proverbs 4:23 GNT).

Imagine riding in a speedboat on a lake with an automatic pilot set to go east. If you decide to reverse and head west, you have two possible ways to change the boat’s direction.  One way is to grab the steering wheel and physically force it to head in the opposite direction that the autopilot is programmed to go. By sheer willpower, you could overcome the autopilot, but you’d feel constant resistance. Your arms would eventually tire of the stress, you’d let go of the steering wheel, and the boat would instantly head back east, the way it was internally programmed. This is what happens when you try to change your life with willpower: You say "I’ll force myself to eat less. . .stop smoking. . .quit being disorganized and late." Yes, willpower can produce short-term change, but it creates constant internal stress because you haven’t dealt with the root cause. The change doesn’t feel natural. Eventually you give up, and go off the diet. There is a better and easier way: Change your autopilot - the way you think.

"Let God transform you into a new person by changing the way you think" (Romans 12:2 NLT).

Your first step in spiritual growth is to start changing the way you think. Change always starts first in your mind. The way you think determines the way you feel, and the way you feel influences the way you act.

"Let the Spirit renew your thoughts and attitudes" (Ephesians 4:23 NLT).

To be like Christ you must develop the mind of Christ. The New Testament calls this mental shift "repentance," which in Greek literally means "to change your mind." To repent means to change the way you think - about God, yourself, sin, other people, life, your future, and everything else. You adopt Christ’s outlook and perspective on life.

"In your relationships with one another, have the same mindset as Christ Jesus" (Philippians 2:5 NIV). 

There are two parts to thinking like Jesus. The first half of this mental shift is to stop thinking immature thoughts, which are self-centered and self-seeking.  Babies, by nature, are completely selfish. They think only of themselves. That is immature thinking.

"Those who are dominated by the sinful nature think about sinful things" (Romans 8:5 NLT).

"Stop thinking like children. In regard to evil be infants, but in your thinking be adults" (1 Corinthians 14:20 NIV).

The second half of thinking like Jesus is to start thinking maturely, which focuses on others, not yourself. In his great chapter on what real love is, Paul concluded that thinking of others is the mark of maturity: "When I was a child, I talked like a child, I thought like a child, I reasoned like a child. When I became a man, I put the ways of childhood behind me" (1 Corinthians 13:11 NIV). Today, many assume that spiritual maturity is measured by how much biblical knowledge and doctrine you know. While knowledge is one measurement of maturity, it isn’t the whole story. The Christian life is far more than creeds and convictions; it includes conduct and character. Our deeds must be consistent with our creeds and our beliefs must be backed up with Christlike behavior. Christianity is not a philosophy, but a relationship and a life, where we practice thinking of others as Jesus did:

"We should think of their good and try to help them by doing what pleases them" (Romans 15:2 CEV).

Don't be selfish; don't try to impress others. Be humble, thinking of others as better than yourselves. Don't look out only for your own interests, but take an interest in others, too" (Philippians 2:3-4 NLT).

Thinking of others is the heart of Christlikeness and the goal of spiritual growth.  This kind of thinking is unnatural, countercultural, and rare. The only way we will learn to think this way is by filling our minds with the Word of God.