Note 6 at 2 Th. 1:5: Many people think that the absence of problems is the true indication of being in God's will, but the scriptures don't teach this (see note 3 at Acts 16:10, p. 668). Paul is saying just the opposite in this verse. Suffering persecution is a manifest token that we are children of God. The persecution doesn't come from God and therefore should not be prayed for or embraced, but it should be expected because, "all that will live godly in Christ Jesus will suffer persecution" (2 Tim. 3:12).

At one time, Paul had been one of the most violent persecutors of the Christians (Acts 22:4; 26:10-11). No doubt he put his efforts into persecuting the Christians who were the most committed. As the true Christians were silenced, it was hoped that those on the fringes would flee in terror. Thus Paul viewed persecution as a manifest token that the individual being persecuted was a true believer. He knew first hand that persecutors don't waste their time on the uncommitted. Therefore, persecution is actually a compliment that our persecutors see proof of a genuine commitment to the Lord in us.