The testimony of a changed life is perhaps the best evidence that God is alive and active today. The fact that at salvation a dead slave to sin is given life and a new nature, comprises the only rational explanation for one who lives in victory and power after a lifetime of defeat.
Take Paul, for example. Our introduction to him is at the stoning of Stephen (Acts 7:58), after which his ardor for the Jewish traditions and hatred of Christianity caused him to wreak "havoc of the church, entering into every house, and haling men and women committed them to prison" (Acts 8:3). This was not just casual opposition, for he was "breathing out threatenings and slaughter against the disciples of the Lord" (Acts 9:1). He was a "blasphemer, and a persecutor |not only of Christians, but of Christ Himself--Acts 9:5|, and injurious" (1 Timothy 1:13).
However, "Christ Jesus came into the world to save sinners; of whom I |Paul| am chief" (1 Timothy 1:15), he said. Paul "obtained mercy" (v. 13), not receiving the punishment he deserved, through "the grace of our Lord |which| was exceeding abundant with faith and love which is in Christ Jesus" (v. 14), even though he was not even seeking God (Acts 9:1-5).
To a greater or lesser degree, God has worked that same work of grace in each life which now belongs to Him. Paul called himself the chief of sinners, but each of us has done or has been capable of equally heinous acts. Through His grace, we are not only rescued from addiction to sin, but rehabilitated and empowered and given, as we see in our text, missions to accomplish that are of eternal significance. Let us "thank Christ Jesus our Lord" with Paul. JDM