What advice about sharing knowledge does the narrator's (John's) father give him at the end of the story and what does John say in regards to what he will do when he becomes the chief priest?

John's father says that the truth should be taught a little at a time. People can only take so much "truth" when they have been used to thinking in a particular way for such a long time. From the text:

Truth is a hard deer to hunt. If you eat too much truth at once, you may die of the truth. It was not idly that our fathers forbade the Dead Places." He was right—it is better the truth should come little by little. I have learned that, being a priest. Perhaps, in the old days, they ate knowledge too fast.

Nevertheless, we make a beginning. it is not for the metal alone we go to the Dead Places now—there are the books and the writings. They are hard to learn. And the magic tools are broken—but we can look at them and wonder. At least, we make a beginning. And, when I am chief priest we shall go beyond the great river. We shall go to the Place of the Gods—the place newyork—not one man but a company. We shall look for the images of the gods and find the god ASHING and the others—the gods Lincoln and Biltmore and Moses. But they were men who built the city, not gods or demons. They were men. I remember the dead man's face. They were men who were here before us. We must build again.