God’s desire for all who know Him is for us to become more like Christ. We do this by first growing in our knowledge of Christ. It stands to reason that we cannot grow to be like someone we don’t know. The deeper our knowledge of Christ, the deeper our understanding of Him, and the more like Him we become. Among other reasons, we are to know and understand Christ so that we will be secure in the faith.
The Apostle Paul reiterates this truth in Ephesians 4:14-16: "Then we will no longer be infants, tossed back and forth by the waves, and blown here and there by every wind of teaching and by the cunning and craftiness of men in their deceitful scheming. Instead, speaking the truth in love, we will in all things grow up into him who is the Head, that is, Christ. From him the whole body, joined and held together by every supporting ligament, grows and builds itself up in love, as each part does its work." This fact is repeated once more in 2 Peter 3:17-18: "Therefore, dear friends, since you already know this, be on your guard so that you may not be carried away by the error of lawless men and fall from your secure position. But grow in the grace and knowledge of our Lord and Savior Jesus Christ. To him be glory both now and forever! Amen." These passages show us that growing in the knowledge of Christ will preserve us from faith-destroying error.
Of course, knowledge alone will not produce a Christlike character. The knowledge we gain from God’s Word must impact our hearts and convict us of the need to obey what we have learned. Romans 12:1-2 tells us emphatically that the process of filling our minds with the knowledge of God not only brings us closer to Christlikeness, but obedience to that knowledge aligns us with the perfect will of God: "Therefore, I urge you, brothers, in view of God’s mercy, to offer your bodies as living sacrifices, holy and pleasing to God—this is your spiritual act of worship. Do not conform any longer to the pattern of this world, but be transformed by the renewing of your mind. Then you will be able to test and approve what God’s will is—his good, pleasing and perfect will."
The natural consequence of knowing and obeying God is that He becomes greater and greater, while we become less and less as we yield control of our lives to Him. Just as John the Baptist knew that “[Jesus] must increase, but I must decrease” (John 3:30), so the Christian grows to reflect more of Christ and less of his own nature. Luke sums it up best when he describes what Jesus told His disciples: "If anyone would come after me, he must deny himself and take up his cross daily and follow me. For whoever wants to save his life will lose it, but whoever loses his life for me will save it" (Luke 9:23-24). The cross was an instrument of death, and Jesus encourages us to take up our cross in order to put to death our old sin nature upon it. God wants us to forget about this world and all its temporary pleasures and be obedient to His Word. Jesus is the living Word (John 1:1), and the Bible is God’s written Word. Therefore, conforming to the Word of God is conforming to Christ.
It is important to realize that becoming more like Christ starts by receiving Him as Savior from our sins. Then we grow in our knowledge of God by reading the Bible daily, studying it, and being obedient to what it says. This process causes us to grow and occurs over an entire lifetime in Christ. Only when we have entered Heaven for eternity with God does this process reach its culmination.