Saved by the Brit - Shabbat 132a

"How do we know that the saving of life supersedes the Sabbath? R. Eleazar b. 'Azariah said: If circumcision, which is [performed on but] one of the limbs of man, supersedes the Sabbath, the saving of life, a minori, must supersede the Sabbath"

The argument that saving a life supersedes Shabbat is not unique to this sugya - however, the inference that saving a life is acceptable from the fact that circumcision is acceptable is fascinating. The logic here implies a quantitative interpretation of saving a life - surely we are intended to infer that circumcision thus 'saves' in some way, in order for it to be used to prove pikuach nefesh. If so, how does circumcision 'save' per se? Is it that it preserves the covenant? Or perhaps that it 'saves' the child from being excluded from the Jewish community? Whether one of these or another, I think the insistence on circumcision as a type of salvation begs to be interpreted, and might shed new light on a ritual that troubles many for what they see as harming a new life rather than saving one. 

Context is everything - Shabbat 130b

Said he [Rabbi Zeira] to him [Rav Assi], But I once asked you and you did not answer me: perhaps in the rush your tradition hurried back to you? Yes, he replied; in the rush my tradition hurried back to me.
-Shabbat 130b

We don't learn in single blocks of information, unconnected from anything else, but rather we add to our webs of knowledge, accumulating connections between things we already understand and that which we are trying to assimilate.

When pressured for an answer, Rav Assi couldn't remember his teaching, but in the flow of the entire argument, from the context of the entire debate, his tradition hurried back to him, and he could give an answer.

To learn something well, it must resonate with other facts within our web of knowledge.

To teach well, we must help our students find those points of connection for themselves, so they too can experience the rush in which learning hurries back to them.