2 The wisdom of his government, the wealth and scope of his teaching, the loftiness of his mind, his unfailing charity—these are the things which St. Leo the Great brought to enhance the fame of Peter's See, to which Almighty God in His providence has also raised Us. And now, on this fifteenth centenary of his death, We feel it incumbent upon Us to highlight his virtues and his immortal merits, confident that these can be of great spiritual value to us all, and increase the prestige and promote the spread of the Catholic Faith.
Source: Aeterna Dei Sapientia (Vatican.va)