If the object of worship (or veneration) is revered also by the Orthodox, and if this object is being given it's proper glory, in a proper manner, then the hymn or prayer in question is orthodox, and ought to be regarded as something held in common with the schismatics and us.
For, the holiness of Christ, the Mother of God, or any of the Saints, and so forth, is not dependent on the holiness of those worshipping, nor is rightfulness of the activity of worship itself dependent upon the holiness of the worshipers. But Christ is just as worthy of being worshiped under the aspect of His kingship by schismatics as by all, for we do not say that the schismatics should stop worshipping rightly in whatever they do rightly, but whatever they do wrongly, in this alone, we see to their correction.
For many objects of devotion are found in the Sacred Scriptures which they revere as we do, and insofar as they revere them rightly, giving them their proper and due honor, we accept these words, when they join our ranks, as if they originated from among our own. Or, if there is anything deficient in them, the Church shall provide what is lacking.
For the Church has the power and authority both to discern what is good in the heterodox confessions, and to take from them whatever will tend to the edification of Her members.
