To be perfect is to be complete. Because God is perfect, He is complete, which means there is nothing that can be or needs to be added to Him. Three is the number of perfection as it also represents the Trinity. As the Father, Son, and Holy Spirit are One, they are complete as One. God is complete as One, which means that we are designed to glorify Him; not add anything to Him, for nothing can be added. Nevertheless, we are called to be one with Him and in Him (see John 17).
We cannot complete ourselves, for we are only complete in Him and Him in us. As we are one with the Lord, we are complete in Him. However, there is a process He takes us through to conform us to the Image of Jesus. In that conformity, we may more readily be one with the Father. That is to say, we will be less likely to resist the Father by our crucifixion with Christ, and be more apt to obey Him (see Galatians 2:20; Matthew 16:24-25). We will more readily walk with Him and go the direction the Lord leads us.
Our completion comes by our willful surrender to God. That is the part we have in the process. Our only part we have in the equation is obedience, which means we present ourselves to Him alone to serve (see Romans 6). Thus, we yield our members as instruments of righteousness, and allow His righteousness to reign in us. Our old nature will never allow this to happen; therefore, it must be crucified. We must count our old man as dead and die daily. There is no other course we can take that will be pleasing to God. Our righteousness is as filthy rags. His righteousness is perfect; therefore, we must allow the righteousness of Christ to reign within us. Our lives are hidden in Christ Jesus, therefore, we are counted as righteous. 1Corinthians 5:21 For He hath made Him to be sin for us, Who knew no sin; that we might be made the righteousness of God in Him (KJV).
By allowing ourselves to be crucified with Christ, we are free to be who we are called to be. We no longer have to try to be righteous, nor try to be someone we are not. We are righteous children of God through Jesus Christ. We do make ourselves holy; we are holy in Him. Nevertheless, the Word clearly says, “Be ye holy for I am holy.” By walking obediently in Christ Jesus, we are holy. By focusing on the things above, we will do the things above, which means we will cease to do those things of darkness. As we walk in the Light as He is the Light, we will do the things of Light. Darkness will have no part in us because the Light dwells in us. We are only complete in Jesus, and that means we can only be perfect in Him. In this way, we will take on His nature and do the things He does. We will be merciful as our Father is merciful. We will be gracious and kind. We will be the expression of His Love. We will be an expression of Who He is because it will be all Him expressing Himself through us!