30 From these words shines forth not only his zeal for the spread of Christ's kingdom, a zeal strengthened by his own and others' incessant prayers, but also his Christian humility, and his close union with the Apostolic See of Rome. This union he carefully and earnestly preserved through his life; it could rightly be called the strong and unshakable foundation of his apostolic labors.
Source: Ecclesiae Fastos (Vatican.va)