Eastern Catholic Churches - Orientalium Dignitas

On 30 November 1894 Pope Leo XIII issued the apostolic constitution Orientalium Dignitas in which he stated:

The Churches of the East are worthy of the glory and reverence that they hold throughout the whole of Christendom in virtue of those extremely ancient, singular memorials that they have bequeathed to us. For it was in that part of the world that the first actions for the redemption of the human race began, in accord with the all-kind plan of God. They swiftly gave forth their yield: there flowered in first blush the glories of preaching the True Faith to the nations, of martyrdom, and of holiness. They gave us the first joys of the fruits of salvation. From them has come a wondrously grand and powerful flood of benefits upon the other peoples of the world, no matter how far-flung. When blessed Peter, the Prince of the Apostles, intended to cast down the manifold wickedness of error and vice, in accord with the will of Heaven, he brought the light of divine Truth, the Gospel of peace, freedom in Christ to the metropolis of the Gentiles.

As Adrian Fortescue wrote, Pope Leo "begins by explaining again that the ancient Eastern rites are a witness to the Apostolicity of the Catholic Church, that their diversity, consistent with unity of the faith, is itself a witness to the unity of the Church, that they add to her dignity and honour. He says that the Catholic Church does not possess one rite only, but that she embraces all the ancient rites of Christendom; her unity consists not in a mechanical uniformity of all her parts, but on the contrary, in their variety, according in one principle and vivified by it."

Leo declared still in force Pope Benedict XIV's encyclical Demandatam, addressed to the Patriarch and the Bishops of the Melkite Catholic Church, in which Pope Benedict forbade Latin Rite clergy to induce Melkite Catholics to transfer to the Latin rite, and he broadened this prohibition to cover all Eastern Catholics, declaring: "Any Latin rite missionary, whether of the secular or religious clergy, who induces with his advice or assistance any Eastern rite faithful to transfer to the Latin rite, will be deposed and excluded from his benefice in addition to the ipso facto suspension a divinis and other punishments that he will incur as imposed in the aforesaid Constitution Demandatam."