Rorate Caeli

Blasts from the past
Brest

1.—Since there is a quarrel between the Romans and Greeks about the procession of the Holy Spirit, which greatly impede unity really for no other reason than that we do not wish to understand one another—we ask that we should not be compelled to any other creed but that we should remain with that which was handed down to us in the Holy Scriptures, in the Gospel, and in the writings of the holy Greek Doctors, that is, that the Holy Spirit proceeds, not from two sources and not by a double procession, but from one origin, from the Father through the Son.
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5.—We shall not debate about purgatory, but we entrust ourselves to the teaching of the Holy Church.
Text of the Union of Brest  
["Articles on union with the Roman Church"]
June 22, 1595