All Christians should agree upon the first point -- no one can come to the Father except through the Son (John 14:6). As for non-Christians, in whom the document stated are in a "gravely deficient situation", this warning is based on simple logic: Jesus is truly the Messiah, Son of God, and Savior of the world; hence other religions are at a disadvantage for not acknowledging Him as such. Pope Pius IX, in 1846, put it himself that "perverse is the shocking theory that it makes no difference to which religion one belongs... They pretend that men can gain eternal salvation by the practice of any religion, as if there could be any sharing between justice and iniquity, any collaboration between light and darkness, or any agreement between Christ and Belial" (QP 15; 2 Cor 6:15). This truth does not mean, as some would nastily infer, that non-Christian religions should be disrespected or their adherents are predestined to hell. Nay! They too have the possibility of salvation since God "desires all men to be saved" (1 Tim 2:4; DI 20); Christ will judge them according to their consciences (Rom 2:14-15).
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Statue of Saint Peter (holding the keys to the kingdom) in Vatican City |
Even if some impatient Catholics wanted to force unity by removing some truths, where does the effort end? Shall you surrender the Pope's supremacy to gain Orthodox Christians? Deny the Real Presence to bring back Protestants? How about rejecting the divinity of Jesus to include Muslims? Disavow God to win atheists? All truth is interconnected. It is impossible to undo one string without everything falling apart. Therefore, Catholics must on guard against the temptation to view Church teaching "as an obstacle to the restoration of fraternal union, things founded on the laws and principles given by Christ and likewise on institutions founded by Him, or which are the defense and support of the integrity of the faith, and the removal which would bring about the union of all, but only to their destruction" (HG 12).
Surrendering controversial doctrine is not an option in ecumenism. Dogmatic relativism or "lowest common denominator belief" cannot bring about real unity and, more seriously, it endangers the salvation of souls. For example, there is only one baptism for the forgiveness of sins, but without correct administration of the sacrament, the assurance of sanctifying grace is thrown in doubt. Must Christians baptize with belief in the Triune God? Is baptism repeatable? Can another liquid besides water be used (like beer)? These questions may seem like doctrinal nit-picking, but, since the Church is entrusted to the salvation of souls, they become necessary to answer.
In conclusion, this document says nothing new. It merely restates what the Catholic Church has already believed since her inception by Christ: "one Lord, one faith, one baptism" (Eph 4:5).
References:
DI = CDF, Dominus Iesus (2000)
HG = Pope Pius XII, Humani Generis (1950)
QP = Pope Pius IX, Qui Pluribius (1846)
UR = Vatican Council II, Unitatis Redintegratio (1964)