Why did the Pelishtim not quarrel over the third well?
Rashbam: Because, as the Pasuk explains, he dug it far away from the previous ones, outside their area and sphere of influence.
Moshav Zekenim: Beforehand, Yitzchak explained to them that the water came up for him three times, so they realized that it is due to him.
Ha'amek Davar #1: The people there were not so evil.
Ha'amek Davar #2: Yitzchak himself dug the first bit, and in this merit, they did not quarrel over it.
Targum Yonasan (to 26:20) says that when they took the first two wells, they dried up. Perhaps they feared to take the third, lest it dry up, and it be clear to all that HaSh-m vindicates Yitzchak. One cannot attribute three occurrences to chance! (PF)
Gur Aryeh: Our verse adds, "[Yitzchak] distanced himself from there." Refer to 26:20:2:7.
Why does the Torah see fit to relate the episode of the wells? What did the three wells symbolize ('Ma'aseh Avos Siman la'Banim')?
Ramban: The three wells of spring-water symbolized the three Batei-Mikdash. 1 'Esek' symbolized the first Beis-ha'Mikdash (over which our enemies fought many battles until they destroyed it; 'Sitnah' symbolizes the second Beis-ha'Mikdash, 2 where our enemies intensified their incessant efforts to destroy it until they ultimately succeeded, and we were driven into a bitter Galus. Whereas 'Rechovos' symbolizes the third Beis-ha'Mikdash, may it be built speedily in our days, which will be built without quarrels and HaSh-m will widen our borders. 3
Malbim: Refer to 26:18:2:2.
Ha'amek Davar: This is a Siman that in exile, expulsion leads to theft with a flimsy claim, theft without any claim (refer to 26:20:2:6), and then increased prosperity and reproduction in the new place.
Like we find in Yirmiyah (17:13) that HaSh-m is compared to a fountain of spring water. Also see Ba'al ha'Turim (to 26: 20,21,22).
What does "u'Farinu ba'Aretz" symbolize?
Ramban: That in the time of the third Beis-ha'Mikdash (in the days of Mashi'ach), all the nations of the world will serve HaSh-m as one!
Ha'amek Davar: Living in a vast area increases reproduction.
Why did Yitzchak go away?
Malbim: It is honorable to avoid quarrels. 1
Ha'amek Davar: He went to a place where the people are not so evil. (He did not specify if this was to avoid quarrels, or due to the bad influence of bad neighbors, or both of these - PF).
What is meant by "Hirchiv HaSh-m Lanu"?
Ha'amek Davar: He enabled us to settle in a vast area. Yitzchak had many slaves on one side in Nachal Gerar, and many slaves on the other side by Be'er Sheva.
QUESTIONS ON RASHI
Rashi writes: "And we will be fruitful (u'Farinu) - As Targum translates, 'v'Nipush.'" What is Rashi explaining?
Gur Aryeh: We should not translate in the past tense, 'we have been fruitful.' Rather, "now that HaSh-m had expanded their borders in the land," the well would make them fruitful in the future.