--I think it was Christ who said it first..."I am the way, the truth, and the light..."
--The Deposit of Truth was begun by the Apostles, to whom Christ gave His authority on Earth, and the Apostles passed it to their followers, etc. The Deposit of Truth means that, while all that is in the Bible is inspired by God, not all that is inspired by God is in the Bible. The Church, then, led by the Holy Spirit, turns to the Scriptures AND to Tradition, as given to us by Christ and the Apostles, and speaks with Authority about matters of faith. Who is the Authority in Protestantism? There are 30,000+ denominations, so you can't say that the Bible is the only authority, as every sect has a different interpretation of it.
--Lying teachers means that those who are not of God will not stand. The "speedy doom" comes to those who oppose God, or speak about/of Christ in ways that are not OF Christ.
From
newadvent.org:
Now in this respect there are several points of controversy between Catholics and every body of Protestants. Is all revealed truth consigned to Holy Scripture? or can it, must it, be admitted that Christ gave to His Apostles to be transmitted to His Church, that the Apostles received either from the very lips of Jesus or from inspiration or Revelation, Divine instructions which they transmitted to the Church and which were not committed to the inspired writings? Must it be admitted that Christ instituted His Church as the official and authentic organ to transmit and explain in virtue of Divine authority the Revelation made to men? The Protestant principle is: The Bible and nothing but the Bible; the Bible, according to them, is the sole theological source; there are no revealed truths save the truths contained in the Bible; according to them the Bible is the sole rule of faith: by it and by it alone should all dogmatic questions be solved; it is the only binding authority. Catholics, on the other hand, hold that there may be, that there is in fact, and that there must of necessity be certain revealed truths apart from those contained in the Bible; they hold furthermore that Jesus Christ has established in fact, and that to adapt the means to the end He should have established, a living organ as much to transmit Scripture and written Revelation as to place revealed truth within reach of everyone always and everywhere. Such are in this respect the two main points of controversy between Catholics and so-called orthodox Protestants (as distinguished from liberal Protestants, who admit neither supernatural Revelation nor the authority of the Bible). The other differences are connected with these or follow from them, as also the differences between different Protestant sects--according as they are more or less faithful to the Protestant principle, they recede from or approach the Catholic position.