The Apostles did not write down every critical point or you could take us to the definitive chapter on trinitarian theology.
Now wait a minute.....
Sure the apostles didn't write down EVERYTHING that happened, but the critical parts? Sure. God had written down what He knows we needed for salvation and growth in Him.
I find it incredibly ironic that a Catholic, of all people would criticize about making stuff up as you go when the Catholic church does that regularly.
A prime example is the bodily assumption of Mary. Their contention is that the Bible doesn't say that it DIDN'T happen, therefore is someone deemed a *church father* proposes it as doctrine, Catholics are expected to buy it because, after all, Scripture doesn't explicitly deny it.
So you're saying trinitarian theology isn't critical? And please show where the Scripture teaches your "Critical Parts" theory.
As far as the Mary issue goes, if she was such a non issue, then why do even the muslims (a pastiche of Jewish and Christian memes to lend authenticity to their new religion) revere her? They were around long before Protestants.
And talk about intellectual dishonesty! Catholics do not claim Mary's unique position BECAUSE Scripture doesn't explicitly deny it. We just point out that the Protestant argument from omission isn't the conclusive lightning bolt they try to make it out to be. And when you stack our "Tradition" against Protestant scriptural silence it becomes pretty obvious why she elicits such histrionics from said Protestants....It would seem God didn't see fit to provide conclusive scriptural refutation to his "born again" children.
In fact, some of my best confutations of Protestant dogma center around Mary.