As famine breaks out in the land of Canaan, Yitzchak takes a leaf from his father's book and makes for the more fertile land of the Pelishtim. He arrives in Gerar where Avraham had dug his wells a generation before. The Torah tells us (Bereshit 26:15-18):
"All the wells that his father's servants had dug in the days of Avraham his father - 'the Pelishtim had stopped them up and filled them with earth.... and Yitzchak dug again the wells of water which they dug in the days of Avraham his father, and which the Pelishtim stopped up after the death of Avraham. And he called them by names as the names which his father called them."
The Torah tells us very little of Yitzchak's life compared to those of his father and son. Of what we are told, this story of re-digging his father's stopped up wells takes a significant place. Why is this?
The Vilna Gaon focuses on the detail that when re-digging the wells, he calls them by the names his father gave them - and that this was out of respect for his father. The Gaon understands this message as analogous to one's behavior: Just as Yitzchak did not even change the names of his father's wells - how much more so should a person not change from the ways of their ancestors The significance of this lesson is seen in that Yitzchak was the only one of our forefathers whose name was never changed (Avram-Avraham: Yaacov-Yisrael).
Rabbenu Bechaya cites an additional explanation. He understands that the wells are analogous to the converts who Avraham brought to monotheism. They came as easily to belief as wells are filled with water with ease. The opening up of a heart previously closed to belief is the digging here. It appears that when the Pelishtim stopped them up and filled them with earth, they closed these converts' hearts to belief and filled them up instead with their own idolatrous ideas. This is the "earth." It was Yitzchak who re-dug those wells, and called them by the names his father gave them - as a convert will take on a new name, so did they to a belief of one God.
Both of these interpretations stress the aspect of continuation. Yitzchak spent his life in continuing that of his father's. However, he did not merely refrain from living a different life - but actually devoted his energies and labors to reworking afresh the toils of Avraham. This was Yitzchak. For certain people it is easy to believe. Coming after them is harder. You often do not have whatever it was that gave your previous generations the conviction to go against the grain. However in such cases, it appears that it is all one can do just not to leave that pattern. Yitzchak teaches that not only is the trait of continuation worthy in and of itself - sometimes merely because it fixes firmly what had not yet taken strong root - but, often one needs to return and go through the same experience and perform the same toils before this part can take root and avoid its up- rooting by others.