Gregory the Great, on Ps 95:12

“The fields and all things that are in them shall be joyful. Then shall all the trees of the woods rejoice”

“When the Lord invites certain ones from villages and streets to the supper, He clearly designates that people who had known how to keep the law under civilized society; but when He commands His guests to be gathered from highways and hedges, He doubtless seeks to gather a rustic people, that is, the Gentiles, of whose signification it is said through the Psalmist: "Then shall all the trees of the forest rejoice before the face of the Lord, because He comes." For the trees of the forest are called the Gentiles, because in their unbelief they were always twisted and unfruitful. Those therefore who were converted from that rustic way of life came to the Lord's supper as if from hedges.”

Imported from an open dataset — not yet checked against the printed edition.