Here.
It's a textbook example of ignorant exegesis, in this case of Colossians 1:24.
Who now rejoice in my sufferings for you, and fill up that which is behind of the afflictions of Christ in my flesh for his body's sake, which is the church
Νῦν χαίρω ἐν τοῖς παθήμασιν μου ὑπὲρ ὑμῶν καὶ ἀνταναπληρῶ τὰ ὑστερήματα τῶν θλίψεων τοῦ Χριστοῦ ἐν τῇ σαρκί μου ὑπὲρ τοῦ σώματος αὐτοῦ ὅ ἐστιν ἡ ἐκκλησία
Paul isn't saying there's anything insufficient or lacking in Christ's afflictions. He's saying he himself is lacking in them, which is why he says to begin with that he rejoices in his sufferings.
Those sufferings fill up what he asserts to be a deficit of them in his experience, "in my flesh" (ἐν τῇ σαρκί μου), which might seem surprising given his statements elsewhere about their ubiquity in his missionary activity. So Paul is clearly speaking a little hyperbolically about himself here. Or perhaps ironically. In comparison with most every one of his contemporaries, he has already suffered much. The point Paul wishes to make is that his service to the church as Apostle to the Gentiles is validated when he experiences suffering and affliction, and so he welcomes those things. The more he suffers for the sake of the gospel, the more the church should know the validity of his calling. "When I am weak, then am I strong", etc.
This is an entirely autobiographical statement by Paul as an apostle, an example of the defense of himself he is wont to make against his opponents, rather than a recommendation for or illustration of the normal Christian life (compare his counsel elsewhere to ordinary folk to live peaceably with all men, live quietly, work with your hands, etc.).
To suggest otherwise is ignorant and needlessly feverish.
