One of the arguments I hear bandied about by skeptics is that the early church would have accepted anything. They weren't sufficiently skeptical about the writings they received and passed along; they were predisposed to take any writing that had a good story behind it. The 27 writings the early church did finally accept as the canonical New Testament haven't been properly screened; they were just accepted at face value by people who were in the habit of accepting things at face value.
This argument does not pass the most basic of all B.S. detectors: the sheer amount of contrary evidence. Don't take my word for it; look at the collected writings of Bart Ehrman, proud opponent of Christian orthodoxy. His book Lost Scriptures: Books that Did Not Make It into the New Testament lists an additional 17 gospels, 5 additional books of acts of the apostles, 13 non-canonical epistles and related writings, and 7 non-canonical apocalypses and revelatory writings. Ehrman's work doesn't list every single piece of early Christian writing, but it does tally up an impressive 42 additional works. If you compare the 27 writings that did make the New Testament with the 42 that Ehrman lists that did not, we find that the church was, actually, fairly selective. If we just work with these two simple numbers -- the list that the early church ultimately accepted and the list that Ehrman proposes -- we find that the church screened out just over 60% of the proposed writings.
It's a legitimate question: On what did the early church screen works as being "in" or "out"? But it's not legitimate to say they weren't screening.