One aspect of lay responsibility is the use of St Vincent’s Canon, which is the universal rule for distinguishing heresy from truth. Its use is in consistent with the responsibility of the faithful and not with an unerring centre of truth. Thus laity using the Canon to determine whether a particular is teaching heresy is an act of responsibility, which, from the above, is an inescapable aspect of a genuine Christian life. It is a cross that must be borne. This is contrary to the notion that a Christian has only to follow the unerring centre of the Church. This does not require theological responsibility apart from the acceptance of the unerring centre as such and obedience to it.
Why an unerring centre insufficient? A Christian must grow to perfection in his entire life, in every aspect “You therefore be perfect, just as your Father in heaven is perfect.” Matt 5:40 “And He gave some as apostles, and some as prophets, and some as evangelists, and some as pastors and teachers, for the perfecting of the saints for the work of ministry, for the building up of the body of Christ, until we all arrive to the unity of the faith and of the knowledge of the Son of God, to a mature man, to the measure of the stature of the fullness of Christ; that we may no longer be infants, being tossed as by waves, and being carried about by every wind of doctrine, by the trickery of men, by craftiness in regard to deceitful scheming, but speaking the truth in love, we may grow up in all things into Him who is the head–Christ–from whom the whole body, being fitted and held together by what every joint supplies, according to the working of the measure of each individual part, causes the growth of the body for the edification of itself in love.” (Eph 4:11-16) All the faithful grow into the fullness of Christ and by the way of the cross. We are all left with trials in every aspect because it is through these that we grow, without such trials we remain children and fail to grow into the fullness of Christ. Also, we each supply to the building of the whole body, so our responsibility extends not only to our own learning but that of the entire body. Although not all are apostles, Popes, Patriarchs or teachers, we all share in the growth of the body as it is our own body. But we must do all in love. An unerring centre removes the responsibility of each and all. There is no need for this responsibility because the faith of the centre is always sure. Thus we cannot all live this responsibility and we cannot all grow fully into Christ because all dogmas point to Christ, not as a concept but as the One in whom all live in fullness. We live the dogma because the dogma is Christ. Every aspect of life in Christ is shared by all.
Thus an unerring centre is not just a disincentive for responsibility it precludes the laity from the fullness of responsibility regarding the faith and hence the fullness of life in Christ. The Church ceases to live, to exist; it dies. (Note: this does not remove the order of the Church into its various ministries and orders. Not everyone is an apostle or priest, not everyone is permitted to teach publicly, nor to offer the Eucharist in the Liturgy but all may teach in private, all offer themselves in sacrifice personally in their daily lives. We all share in the life of the Church but the public aspects are restricted to those called to show forth the fullness of the Mystery of the Church in Christ. An infallible centre is not able to be shared in private but each and all. Neither does this negate the infallibility of the Church or the surety of the Faith. It places this is Christ, whose infallibility is manifest in the weakness of man without losing His infallibility or the freedom of man. All men support each other in love so that through this love we may grow into Christ. An unerring centre does not need support and so puts itself apart from this bond of mutual love and the unity of the faithful.)