For two reasons Paul is confident his work among the Thessalonians was not in vain. Firstly, there was visible evidence of the work of God in their lives. Secondly, and most significantly, they were chosen and loved by God, just as Paul, Silas and Timothy were. The first is the fruit and evidence of the second. For those in Christ, we too can just as sure and certain that our labours in life and faith are not in vain, for we too have been chosen and loved by God. Take a moment to look and see the work of God in your own life and give thanks to him for his grace and love towards you.