“16 He that heareth you, heareth me; and he that despiseth you, despiseth me; and he that despiseth me, despiseth him that sent me. 17 And the seventy-two returned with joy, saying: Lord, the devils also are subject to us in thy name.” — Luke 10
Christ predicated His post-Ascension authority upon the reception of His words by way of His own Apostles. Whoever heeds the Apostles, heeds Christ. Running verse 16 as a modus tollens, it follows that whoever does not hear the Apostles, does not hear Christ.
Now, according to Protestants, we hear the Apostles, and thus the authentic, binding teaching of Christ, solely in the canonical Scriptures. (Who made that canon in the first place is its own famous can of worms, but let’s ignore that problem for now.) The problem is that the Scriptures do not contain writings from all the Apostles. Therefore, with Scripture alone, it is impossible to hear the same Apostles to whom Christ said, “He that heareth you, heareth me.” If the only means by which we can hear Christ is by way of hearing the Apostles, and if the only way we can hear the Apostles is by reading the Scriptures, then the Scriptures must contain the complete voice of the Apostles–yet they do not.
Does this mean that the Apostles were silent, and therefore the voice of Christ fell mute upon the world without their contributions to Scripture? No, for there is a well established means by which all the Apostles authoritatively echoed Christ for our benefits, namely, by the ecclesial Tradition which flowered as a result of their historic missionary efforts.
The objection may be that we still need some canon besides these pillars of Tradition to sort out the complexities of what those apostolic roots–as the voice of Christ–bequeathed to the Church. This, however, is irrelevant because the Church agrees that Tradition is not enough. Just as there is an undivided unity of Persons in God (ad intra), so there is an undivided unity of media by which God as Beauty, Goodness, and Truth is known in the Church (ad extra). Scripture is the Lamp of the Spirit lighting the Way of Tradition, but that Lamp is held by no other Hand than the Magisterium qua the concrete endurance of the Apostles’s foundations. If the Lamp is set down upon the Way, the Church stays in one frame of the Tradition, chained to that patch of the Kingdom (rather like the Eastern Orthodox). The Hand is equally vital for the Journey to the Father. Likewise, if the Hand walks the Way without the Lamp, the Church will wander blindly, rather like Gnostics. Similarly, if the Hand carries the Lamp into the forest simply to enjoy the warm glow without obeying the contours of the Way, it will become lost in the immediacy of its bright but aimless short-sightedness (i.e. Protestantism).
So, while the triune nature of Christ’s headship–Scripture, Tradition Magisterium–does not of itself remove the need for working out apparent contradictions and growth into the truth, it does at least provide all the resources Christ knew we would need in order to overcome any obstacle on the Journey to the Father. Never forget that when Christ said the gates of Hades would not prevail against the Church built on the supernaturally faithful Peter, He gave us an offensive mandate, not a merely defensive assurance. As Stephen Beale notes,
Reading hell in this way reverses how we see the gates—the gates are not to be thought of as a monstrous opening from which hell vomits forth demonic armies upon the Church. Instead, the gates of death could be thought of as prison doors that once barred the way to heaven. According to this interpretation, Jesus is saying that the gates of hell can no longer hold back members of the Church—just as they could no longer contain the fathers in limbo.
So, boys and girls, don’t take any bunkum from the powers of darkness, knowing that We Win. To that end, never surrender the trident given us by Our Lord for the Battle: a Traditionally informed Scriptural faith that is obedient to the Magisterium.