“For by one offering He has perfected for all time those who are being sanctified.” (Hebrews 10:14 LSB) https://accordance.bible/link/read/LSB#Heb._10:14
No man works his way to heaven for the work required to enter heaven has been accomplished by Him Who lived a perfect life. This perfect life was offered unto God as a sacrifice for the imperfect lives, lives of rebellion against God, all men live. Jesus dying on the cross was the perfect life of God sacrificed for the sinful lives of men in order to perfect men for becoming acceptable to God. Jesus has paid the price for our disobedience and has appropriated to us for all time His perfect life making us and making possible, our acceptance to God. We are declared perfect because of the perfect life, work, of Jesus appropriated to us. Have we received this pardon, this gift of God for the forgiveness of our sins? Are we living for God, are we being sanctified, that is, are we growing in likeness to that of Jesus? If we are then we can rest assured we are accepted by God but if we are continuing to live self-centered lives, ignoring God and His commands, we have no reason to believe we have indeed been perfected by God. A practical self-assessment of our sanctification would review our love for God measured by our time with God in scripture reading and study, alone and with His people in the church. If we are not with God now we may not be with Him later. Likewise, we are being sanctified if we are serving God, by doing His work with His people for accomplishing His will upon earth as it is in heaven. This is the work of winning people to Jesus and discipling them in their faith. Are we sharing Jesus with people and helping people grow closer to Jesus? If so, we are being sanctified as those already declared perfect, if we are not, we have no reason to believe we are truly God’s children for we are not doing the work of God as commanded by the Son of God Who is our Lord. Again, these ‘works’ do not gain us entrance into heaven but reveal that heaven has entered our lives and is now bearing fruit through our lives as evidence of God’s work in our lives. In Christ we are perfect, in this world we are revealing that perfect work of Christ through our work with Him and for Him that reveals Him in the world.