"Now may the God of peace himself sanctify you completely, and may your whole spirit and soul and body be kept blameless at the coming of our Lord Jesus Christ. He who calls you is faithful; he will surely do it." -1 Thessalonians 5:23–24
This is both a prayer from the Apostle for the church, and a declaration of God's promise to those who are believers in Jesus. God will sanctify, change, and make you more like Jesus completely. Even when we are called and empowered to pursue holiness, we can rejoice that the Lord is using all of it to sanctify us because it is his faithfulness that matters.
In Jesus, because of his sacrifice on the cross for you, you are kept blameless and will stand before the throne of heaven justified. As we wait for that day, he is working in us transformation — we are becoming more Christ-like, and the end point is completion, the perfection we were meant for in the beginning.
Today, we might not notice much of the change, but we can trust in the faithfulness of God. He will do it. Rest and rejoice in that truth.