Having acknowledged his friends' suffering by offering a christological reason for it, Paul now returns to the urgent matter at hand: the appeal in verse 27 that in the face of the opposition that is causing suffering, they stand firm in the one Spirit, contending for the gospel as a united body.
It is instructive to watch Paul deal with such matters, especially noting how he refrains from our own tendencies toward "saint-bashing" when the sins of others are clearer to us than our own. Again, their relationship to him as friends and his need to speak into their present situation combine to create another long and complex sentence. But the way the parts work is easy to see.
Verse 1 offers the basis of the appeal, which has to do (apparently) with their own trinitarian experience of God: Christ's comfort, God's love and their common sharing in the Spirit. But it is also based on their long-standing relationship with Paul, who has shared both the suffering (1:30) and these same graces with them, and now looks for tenderness and compassion from them.
The concern of the appeal is expressed in verse 2, where he piles up three phrases that all say essentially the same thing: that their community life should be characterized by unity of mind and love. Only thus can they complete Paul's own joy.
The content of the appeal (vv. 3-4) describes, first, those expressions of our human fallenness that altogether militate against unity within the household of faith, selfish ambition and vain conceit; and, second, those virtues necessary for it to happen, love and humility, which find concrete expression as God's people learn to live as Christ, to care for the needs of others as the matter of first priority—all of which will be gloriously displayed in the Christ narrative that follows.
IVP New Testament Commentaries are made available by the generosity of InterVarsity Press.