by St. Justin Popovich
The Holiness of the Church
... The flow of history confirms the reality of the Gospel: the Church is filled to overflowing with sinners. Does their presence in the Church reduce, violate, or destroy her sanctity? Not in the least! For her Head—the Lord Christ, and her Soul —the Holy Spirit, and her divine teaching, her mysteries, and her virtues, are indissolubly and immutably holy. The Church tolerates sinners, shelters them, and instructs them, that they may be awakened and roused to repentance and spiritual recovery and transfiguration; but they do not hinder the Church from being holy. Only unrepentant sinners, persistent in evil and godless malice, are cut off from the Church either by the visible action of the theanthropic [i.e. of the God-Man] authority of the Church or by the invisible action of divine judgment, so that thus also the holiness of the Church may be preserved. "Put away from among yourselves that wicked person" (I Cor. 5:13).
In their writings and at the Councils, the holy fathers confessed the holiness of the church as her essential and immutable quality. The fathers of the Second Ecumenical Council defined it dogmatically in the ninth article of the Symbol of Faith. And the succeeding ecumenical councils confirmed it by the seal of their assent.