If I were god I'd be really offended by this line of logic;
And since the entire Bible was inspired by the speaker of those parables, it makes sense that the entire Bible would be written in the same way that Christ's parables were spoken. In a way that would give some the opportunity to find fault and stumble and others the opportunity to learn "the secrets of the kingdom of God."
Okay, let's first take an example which shows how fallacious the reasoning given here is. Say the parable of the Good Samaritan and Numbers Chapter 31.
In the the story of the Good Samaritan, Jesus shows how two supposedly upstanding members of the community bypassed the victim of a violent assault whilst a third person, not even a member of the same community, showed far greater love by lending assistance.
Now, unless one were pretty unreasonable, it would be hard to be stumbled by this, showing the assertion in the above quote ("In a way that would give some the opportunity to find fault and stumble...") to be false.
At the same time, Numbers 31 shows it's very easy to find the opposite in the Bible, a passage that it is hard for a reasonable person to NOT be 'stumbled' by. In this chapter we are told how YHWH asks the Israelites to kill all the men, women and boys, but to keepoa live the virgin girls. Anyone who knows their Mosaic Law will realise there are rules for how female captives may be married off. Likewise, anyone knowing their history will realise that 14 was probably the average age of marriage at that point, and that as far as the Mosaic Law was concerned, the marriage of captives was not neccesarily with their consent.
So, we supposedly have the Lord God telling the Israelites to go and get some little girls, whom they could forcably marry; a wonderful provision, being raped by the same people who hacked your entire family to death. Wrong in Rwanda. Wrong in Bosnia. Wrong in the Palestine -both then and now.
Any reasonable person would be appaled or 'stumbled' by this, yet the above quote implies that such a stumbling would be deliberate on account of the author of the Bible, an intentional result of the way the account is written, to presumably sort those who love god from those who do not.
Quite how such tomfoolery is neccesary when we are told god can see into our hearts, I don't know, but that's just an aside.
Rather than say, "well, maybe this is just what a person of that period thought was god's will, but looked at today is pretty standard as far as the time-period goes, and obviously isn't direct inspiration as there's no way a god of love would approve of child rape like that", the writer of the above quote is asking us to believe that god (who can see our hearts) either put this into the Bible (when it didn't happen) to test us OR (if it did happen) had this happen to test us.
A simple choice; the Bible was written as you'd expect it to be written at the time it was written, or god plays silly games.
Whilst it is pretty obvious which is the most logical choice of the two above, accepting the Bible "was written as you'd expect it to be written at the time it was written" (i.e. is not inspired of god and accurate) means letting go of all the exclusivity and specificity. If you accept that, the Bible becomes just another guide by men who sought god.
Doing this, opening one's heart and mind to trying to conceive what god may be like free of the illogical restrictions of texts written by bronze-age goatherds, is directly against the political and religious agenda of many conservative and fundamental Christians.
By insisting on the divine authorship and accuracy of the Bible, they can insist that their (interpretation) is correct and that those disagreeing with it are wrong, which normally means bad, which normally means we should change laws so people are punished for acting in that way.
Thus, in what is one of the most absurd contradictions of belief one can see (and it's not just restricted to Christians), people insist on a strict literalistic interpretation (where disagreement with the text is a sign that you're not the right sort of person), and become worshipers of a book, rather than using the supposedly god-given discernment they have to distinguish fact from fable and to distinguish guidance to live our lives in a more spritual manner from blood-thirsty ancient texts, and trying to worship god in spirit.
It's really sad, and gets on my nerves, just as the Pharasees really got on Jesus' nerves for doing fundamentally the same thing.
Strain the gnat and swallow the camel, isn't it?