today's other readings are Psalm 126 and Lk. 13: 18-21
I have been assured by more than a few women, including my mother, that there is no pain to be compared with the pain of being in labour. And I will certainly take their word for that.
Obviously St. Paul did not know such pain, but he must have witnessed it in the lives of the women he knew. Hence uses this image to describe how we, and all of creation, "groan inwardly wile we wait for adoption, the redemption of our bodies". This redemption he describes is the "glory about to be revealed to us".
I sometimes ponder what this redemption will be like, and while some may view such speculations as not useful, I do get excited by the possibilities. One word that always come to mind is joy - sheer, pure joy, a joy that might be compared to the feelings of a mother holding her new born daughter or son. Pure joy!