Colossians 1:29

εἰς ὃ : to achieve which end. κοπιῶ expresses toil carried to the point of weariness. ἀγωνιζόμενος : a metaphor from the arena. Meyer takes the reference to be to inward striving against difficulties and hostile forces. Perhaps both inward and outward struggle are referred to (De W.). κατὰ. The struggle is carried on in proportion not to his natural powers, but to the mightily working energy of Christ within him. ἐνεργουμένην : a dynamic middle (cf. Colossians 1:6).