This is a good point, and also a good reason for talking to real-life teachers, who tend to challenge one's assumptions better than books do...boris wrote: Suppose, I am a puthujjana I have some vision what is Dhamma and what is not Dhamma. Then I come to some passage which contradict all my understanding. I can explain this contradiction saying that it is because the text has suffered editorial changes. Or even to refuse accept that such Sutta comes from the Lord Buddha. By this means I can be glad and happy, that there is no contradiction in my understanding of Dhamma. And even it may be so. But unfortunately it is also quite possible, that this contradiction is due to my wrong understanding of Dhamma. With this approach, each contradiction should be interpreting as a signal that it something wrong with my understanding of Dhamma.
On the other hand, there is some validity in the warning against taking passages that only appear a few times in the entire canon as being supremely important. Certainly, they are useful challenges, but not necessarily the right thing to concentrate on.