There was a time when family homes in Ireland had a picture of the sacred Heart and perhaps an altar of holy pictures. At one time, when I was growing up, I had an altar in my bedroom.
These holy pictures depicting various saints, had a yellow rimmed halo around the saints head. This halo was not attached to them but radiated out from their heads and was expression of their sanctity. Somehow these people had become so transparent to the sacred that the invisible world of divinity was shining through them.
In many religious traditions, the glory of God is manifested as light. For me there were moments during Pope Francis’ visit last week that he seemed to radiate that very light.