Which is a manifest token of the righteous judgment of God, that you may be counted worthy of the kingdom of God, for which you also suffer:
All Commentaries on 2 Thessalonians 1:5 Go To 2 Thessalonians 1
Thietland of Einsiedeln
AD 1000
so that you may be held worthy of the kingdom of God, for which you also suffer
The persecutions and tribulation did not make them worthy, but rather the grace of God that bestows to them the power of enduring those things patiently.