...Cranfield is probably right that what is meant are utterances or groanings that are imperceptible to the believer. The Spirit groans along with the believer, just as the believer groans as part of fallen creation.N.T. Wright has noted how we as believers in Jesus groan with the rest of creation for God's full renewal of all things, which begins with the redemption of our bodies in the resurrection.
Ben Witherington III, Paul's Letter to the Romans: A Socio-Rhetorical Commentary, 226
When we seek to pray, just groaning should never be despised. This can be among the most powerful kind of praying and prayers. Even though we may not be uttering a word, not knowing what to pray, just our groans to God can be taken by, and/or come from the Spirit, who intercedes in us according to the will of God.
I often feel near groaning, at least a good part of any given day. And such often is the case when I am troubled in trying to pray for someone or something. But we should turn our groans "upward" in prayers to God, seeing them as something God can take as we think of those in need of God's intervention. And for ourselves as well.
I think I've found this helpful. When my prayer life may seem dormant, groanings may end up finding their way in and out of the throne room of God for the good of others, and the world, as well as ourselves.
How do you look at groaning as potentially being a most powerful kind of prayer? Or any thoughts on this?