6 The Supreme Pontiffs have issued many documents reminding those in sacred orders of the greatness of their priestly office, and pointing out the safest and surest way for them to carry out their duties properly. To recall only the more recent and more important of these, We would like to make special mention of the Apostolic Exhortation of St. Pius X of happy memory entitled " Haerent Animo ," (3) issued early in Our priesthood, which urged Us on to greater efforts to achieve a more ardent devotion, and the wonderful encyclical of our predecessor of happy memory, Pius XI, that began with the words " Ad catholici sacerdotii ," (4) and finally the Apostolic Exhortation " Menti Nostrae " (5) of Our immediate predecessor, along with his three allocutions on the occasion of the canonization of St. Pius X that give so clear and complete a picture of sacred orders.(6) Undoubtedly you are familiar with all of these documents, Venerable Brethren. But permit Us also to mention a few words from a sermon published after the death of Our immediate predecessor; they stand as the final solemn exhortation of that great Pontiff to priestly holiness: "Through the character of Sacred Orders, God willed to ratify that eternal covenant of love, by which He loves His priests above all others; and they are obliged to repay God for this special love with holiness of life... So a cleric should be considered as a man chosen and set apart from the midst of the people, and blessed in a very special way with heavenly gifts—a sharer in divine power, and, to put it briefly, another Christ... He is no longer supposed to live for himself; nor can he devote himself to the interests of just his own relatives, or friends or native land... He must be aflame with charity toward everyone. Not even his thoughts, his will, his feelings belong to him, for they are rather those of Jesus Christ who is his life." (7)
Source: Sacerdotii Nostri Primordia (Vatican.va)