>>54742548I refer you to what I posted to the Brit about St Optatus on Donatism. The measure by which St Optatus determines whether it was the Catholic Church who had strayed from the Donatists, or whether it was the Donatists who had strayed from the Catholic Church is by using the Chair as the point of reference. The Chair in question is the Cathedra Petri - the Chair of St Peter - or, the episcopal see of the Bishop of Rome.
St Optatus concluded that because Majorianus (a Donatist bishop in Carthage) was not in communion with the Chair of St Peter, it was he who had broken fellowship with the Catholic Church, and was therefore in schism from the Church, and not the Catholic Church which had broken fellowship and was in schism from the Donatists.
Applying St Optatus' logic to the East-West Schism, one need only use the Chair of St Peter as the point of reference as St Optatus did.
Now, regarding Vatican II and the question of modernism, I refer you to the assurance Our Lord gave to St Peter: "And I say to thee: That thou art Peter; and upon this rock I will build my church, and the gates of hell shall not prevail against it." (Mt 16:18) Do not fall into the error of the sedevacantists, who do not keep faith in the assurance of Our Lord but are doubtful. The Holy Spirit guides the Bride of Christ, and though our Accuser has always sought to infiltrate Her and corrupt Her - as he continues to do to this day - his head will be crushed as it is written.
