Zac Poonen emphasizes the process of progressive sanctification, explaining that while the Law revealed humanity's inability to meet God's standards, it also pointed to the need for a Savior. Under the new covenant, believers are empowered by the Holy Spirit to not only understand God's commandments but also to desire and fulfill them. Poonen highlights that sanctification is a cooperative process where God works in us, and we must actively participate in cleansing ourselves from sin. The ultimate goal is to reflect the character of Christ, producing the fruit of the Spirit in our lives. This journey leads to increasing light and transformation into Christ's likeness.

Jesus told His apostles to teach others to obey all that He had commanded (Matt. 28:20). One who loves the Lord will first of all seek with all his heart to find out what those commandments are; and then he will seek to obey them (John 14:21). Under the Law, God gave man commandments, but not the power to obey them. Why then did God give the Law? Only in order that man might discover that he's unable to come up to God's standards, and thus see his need of a Saviour and a Helper. "The Law has become our tutor to lead us to Christ" (Gal. 3:24). But now God has made a new covenant with man. And He has given us, not only commandments, but also an Example in the person of our Lord Jesus Christ. Jesus demonstrated by His earthly life that it is possible for us to obey all of God's commandments. God has also promised under the new covenant to put His Laws into our minds and to write them upon our hearts (Heb. 8:10). He does this through the Holy Spirit dwelling in us. The Holy Spirit is our Helper Who not only shows us what the will of God is, but also gives us a desire to do that will and grace to obey all of it too. God is the One Who is going to sanctify us entirely (1 Thess. 5:23). We can't do it on our own. We have to depend on Him - for He is the One Who works in us giving us both the desire as well as the ability to do His will. But we have to "work out our salvation with fear and trembling" (Phil. 2:12,13). We have to work out what God works in, for He hasn't turned us into robots! God cleanses us from the guilt of sin. But we are commanded to "cleanse ourselves from all defilement of flesh and spirit, perfecting holiness in the fear of God" (2 Cor. 7:1). We have to do this, as and when we get light on any defilement within us. It is thus, as we "by the Spirit, put to death the deeds of the body" (Rom. 8:13) that the fruit of the Spirit - love, joy, peace, patience, kindness, goodness, faithfulness, gentleness and self-control - will become more and more manifest in us. This is what it means to be transformed into the likeness of Christ. Thus our path will become one of increasing light (Prov. 4:18). This is the glorious way of sanctification that God has made for us.