“Why is the author saying this here?” I don’t know if it’s possible to ask this question too often. Re today’s Romans text, it helps me recognize that vv.26-30 are tightly connected to the previous verses, rather than, say, v.28 as a stand-alone consolation for Difficult Times, and vv.29-30, a Handy Summary of the Process of Individual Salvation.
The previous verses: regularly encountering suffering and futility, together with the whole creation we’re groaning, even as we await the redemption of our bodies. In that situation we regularly don’t know how to pray, and in the midst of our weakness and incoherence the Spirit is interceding. That part of prayer that I find the least satisfying and could judge the least productive is where the Spirit is actively engaged.
And it’s in these least satisfying and apparently least productive situations in which God is working all things for good.
These least satisfying and apparently least productive situations: they’re part of being “conformed to the image of [God’s] Son, a process in which God’s initiatives restore, rather than threaten, my agency.
And glory, with which the text ends? I think Wright nails it: “the purpose is never simply that God’s people in Christ should resemble him, spectacular and glorious though that promise is. As we saw in vv. 18-21, it is that, as true image-bearers, they might reflect that same image into the world, bringing to creation the healing, freedom, and life for which it longs. To be conformed to the image of God, or of God’s Son, is a dynamic, not a static concept. Reflecting God into the world is a matter of costly vocation.”