who will pay the penalty: eternal destruction from the face of the Lord and from the glory of his might,
The Thessalonian Christians continue to grow in faith, love and endurance, in spite of the constant persecution they suffer; and Paul continues to talk about them as an example that should challenge others (1:1-4; cf. 1 Thessalonians 1:3,1 Thessalonians 1:6-7). He encourages them to keep moving forward, and points out that their suffering is proof of the genuineness of their faith. Their endurance shows that they are worthy to inherit the kingdom of God. In his righteous judgment God uses sufferings to bring his people to maturity, but by the same righteous judgment he will punish those who persecute them (5-6).