Why can't I put my prayers into words?
Because in our infirmity we don't know what we should pray for as we ought; we have an idea of what we want but cannot put it into words. In those times the Holy Spirit intercedes for us with groanings that cannot be uttered.
Les explains that God can strengthen us in our places of infirmity, for we know not what we should pray for as we ought. There come places in life where we just don't know how to pray. We have an idea of what we want, but we can't put it into words. He advises, when you get to that situation, just be quiet, just shut up, and let the Holy Spirit commune for you. This is not necessarily a tongues experience, not what Paul's talking about. But we get to a place where the Holy Spirit actually intercedes on our behalf. Les notes this is a different intercessory power than John talks about in his little epistle, 1 John 2.
Likewise the Spirit also helpeth our infirmities: for we know not what we should pray for as we ought: but the Spirit itself maketh intercession for us with groanings which cannot be uttered.
More Questions
What does Romans 8:26 mean when it says we don't know what to pray for?
Paul is saying that there are times in life when we just don't know how to pray—we have an idea of what we want but cannot put it into words.