- A teacher brings out what is already there in the student—the Latin etymology of 'educate' is horticultural—rather than pouring in. The teacher provides environment & stimuli; the student the rest.
- Answer questions with questions--the student learns by doing and thinking-through, rather than simply adding a set answer as one more log on the mental pile. "Give them a fish and they eat for a day; teach them to fish and they eat for a lifetime."
Although the words don't have the same root according to the OED, 'sacred' certainly sounds like 'secret', and they come from words which have very similar meanings. 'Sacred' comes from L. 'sacer' and means to set apart. 'Secret', as you know, comes from L. 'secernere', which means to separate, or to divide off. Perhaps the Latin words 'sacer' and 'secernere' are cognates, and the OED simply does not trace the words far enough back (it is Latin after all, and not English).
Also, the word 'share' can mean to divide, according to the OED. Consider a ploughshare, which cuts the soil. Thus, both words in the title can mean to divide. This title is doubly about division! In this sense, it could be that the secret sharer is the one who destroys the secret, rather than distributes or keeps it. It's a title that opposes and divides itself in a number of ways. It was fun looking into these things.