Some notes from Keeping in Touch, Parshas Toldos:
Two parshas begin with the word "Toldos." The parsha detailing Isaac's life gets called Toldos because of his special way of creating a legacy, ie a life of inner meaning that inspires others.
Isaac's divine service was inward. This is the symbolism of wells. He led via the example of having an inward focus and finding the Godly core. "In this manner, the awareness of G-d becomes an integral part of one's life. It does not remain dependent on the teachings of others, but comes from one's own insight. This in turn enables one to realize the G-dliness present in every element of existence."
"Indeed, the awareness inspired by Isaac was more permanent than that generated by Abraham, for it came from the people themselves."
Lubavitcher Rebbe