... he who began a good work in you will bring it to completion at the day of Jesus Christ. —Philippians 1:6
We have the assurance of God’s Word that we are not yet what we will be one day (1 John 3:2). Paul tells us that God will complete the work which he began. He doesn’t just get us in the door. He will see our salvation all the way through. And the reality of our union with Christ reinforces our hope in this truth.
John Murray writes:
There is no truth, therefore, more suited to impart confidence and strength, comfort and joy in the Lord than this one of union with Christ. It also promotes sanctification, not only because all sanctifying grace is derived from Christ as the crucified and exalted Redeemer, but also because the recognition of fellowship with Christ and of the high privilege it entails incites to gratitude, obedience, and devotion. Union means also communion and communion constrains a humble, reverent, loving walk with him who died and rose again that he might be our Lord (Redemption Accomplished and Applied, p. 171).
The truth of our union with Christ imparts confidence for at least two reasons. First, and more catalytic, it promotes sanctification through our fellowship with God. Second, and more inherent, if we are united with Christ we will certainly be conformed to his likeness.
The knowledge of our union compels us to commune and draw near to God, for indeed we are welcomed into the Trinitarian fellowship as creatures of grace (1 John 1:3). The sheer fact of our union is a ground for ethical instruction (Romans 6:4). It is a glorious foundation that constrains how we live in a fallen world—dead to sin and alive to God, no longer slaves of impurity but now slaves of righteousness (Romans 6:17-19).
And we really are in Christ. We have been transformed, now found in him, not having a righteousness of our own (Philippians 3:9), seated with him in the heavenly places (Ephesians 2:6). We are being transformed from one degree of glory to another (2 Corinthians 3:18), pressing on toward the goal for the prize of the upward call of God in Christ Jesus—conformity to his image (Philippians 3:14). For this is that to which we have been predestined, to be conformed to the image of Christ (Romans 8:29). Here is the purpose of our election—chosen in Christ before the foundation of the world, that we should be holy and blameless before him in love (Ephesians 1:4).
God’s purpose for us—that which he is working to complete—is grounded in our union with Jesus.
Yes! Yes. He will complete the good work that he began in us. Amen.