Source · the work in full
Homilies on the Epistle to the Romans
Chapter 3
Romans 3
Here he shows God's power, in that He has not only saved, but has even justified, and led them to boasting, and this too without needing works, but looking for faith only.
You arrive at the cited line; the whole work is yours to read around it. The text is set from the cited public-domain edition.