Commentary Par XXIV 34-36

From this tercet we realize that the 'everlasting light' (we remember that this light was the most brilliant among its companions in the Church Triumphant at [Par XXIV 21]) addressed by Beatrice is St. Peter.  For Jesus left the 'keys of the kingdom' (Matthew 16:19) to Peter.  In the tradition of Roman Catholicism, this signified that Jesus picked him to be the first pope, presiding over, among other things, the departure of the saved and damned souls for the afterlife.