2 Thessalonians 1:6

If so be that it is a righteous thing with God

(ειπερ δικαιον παρα θεω). Condition of first class, determined as fulfilled, assumed as true, but with ειπερ (if on the whole, provided that) as in Romans 8:9; Romans 8:17, and with no copula expressed. A righteous thing "with God" means by the side of God (παρα θεω) and so from God's standpoint. This is as near to the idea of absolute right as it is possible to attain. Note the phrase in verse 2 Thessalonians 1:5.To recompense affliction to them that afflict you

(ανταποδουνα τοις θλιβουσιν ημας θλιψιν). Second aorist active infinitive of double compound αντ-αποδιδωμ, old verb, either in good sense as in 1 Thessalonians 3:9 or in bad sense as here. Paul is certain of this principle, though he puts it conditionally.