CAUSES OF DOCTRINAL DEVELOPMENT.
3. We must hold that wherever the Apostles preached, they instructed their converts sufficiently in the faith by their own teaching, and left an adequate deposit of Christian doctrine in the several churches they founded. Still, we can see from Paul's Epistles how much had remained to be supplemented, and how the implicit teaching that he had imparted on various points of doctrine needed to be afterwards explained and further developed. The Apostle is frequently led to dwell in his Epistles upon certain matters which the circumstances of those to whom he wrote made it more needful to explain. He solves their objections and difficulties, and answers the questions they have raised. But how many more inquiries might they not have proposed had their doctrinal investigation been more extended and their theological science more profound. And how many other things might he not have said by way of more fully explaining those revealed truths which he had taught them explicitly in his oral instructions. Now this is precisely what the Church has been continually doing by her definitions of faith, the teaching of her doctors and theologians, and through the ordinary Magisterium.
We should hold that the Apostles had the fullest knowledge both extensively and intensively of Christian truth. No theologian to the end of time will ever know more than they did. To affirm that any in after time could have a more explicit faith than the Apostles, would, as Suarez teaches, be temerarious.*
* Disp. ii.sect. vi. 13: "The Apostles' apprehension of doctrine was keener, more definite, more precise, than any which human words can possibly convey; it was the Holy Ghost's direct impress on ther intellect and their heart. They expressed it, however, in words, as best it could be expressed... In communicating the doctrine to their immediate disciples, they would (as all good teachers do) pay special attention to the antecedent circumstances, acquirements and temperament of those disciples. It is a question, what form of words is in itself the more appropriate, the less inadequate, to convey some sacred idea; it is quite another question, what words would most effectively convey it to this or that particular disciple or body of disciples." -- Dublin Review, October, 1865, p. 341.