“Go therefore and make disciples of all nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit,teaching them to observe all that I have commanded you–wait, on second, thought, just baptize and forget the rest.”
#ThingsJesusNeverSaid
Baptism begins the incorporation into Christ and the Church, creates an indestructible bond with the Church, and was instituted to lead one to full membership, but alone it does not make one a member. From the Vatican II decree on ecumenism:
Baptism therefore establishes a sacramental bond of unity which links all who have been reborn by it. But of itself Baptism is only a beginning, an inauguration wholly directed toward the fullness of life in Christ. Baptism, therefore, envisages a complete profession of faith, complete incorporation in the system of salvation such as Christ willed it to be, and finally complete ingrafting in eucharistic communion.
Because of the sins of men, Baptism is now administered apart from and without its intended completion. Incorporation is begun, but not finished.
In addition to Baptism, to have fellowship or communion with Christ in His Body, you must have fellowship with those who have fellowship with Him (1 John 1:3). We are forbidden, therefore, from schisms and dissensions and must be united in belief (1 Cor. 1:10). Heresy and schism, therefore, also exclude from salvation (Gal 5:20-21; Titus 3:10-11).
Furthermore, while Christ is the head of the Church, He has also willed that the Church be led by men (Acts 20:28). He put St. Peter in charge of His one and only flock (John 21:15-17)–therefore, to be a member of Christ’s flock is to be a member of the flock tended by those who continue to exercise Peter’s ministry.
Our sins are to be forgiven through the ministry of the Church (John 20:21-22) and the faith is to be taught by those with succession from the Apostles–those who have been sent (Rom 10:15). Going out without being sent (like Protestant ministers do), on the other hand, is harmful to souls (Acts 15:24).
Certainly heresy and schism, like all sins, must be properly deliberate and volitional for their to be guilt (a person in good conscience doing their due diligence to seek the truth about God and his Church would not be guilty of such sins if committed in error). Seeking the conversion of Protestants is therefore good for both outside the Church through their own fault and those in good faith (the latter, it brings them their hearts’ greatest desire).