פּירוש אויף בראשית 26:19

And Isaac’s servants dug in the valley and found there a well of living waters. The Ramban writes, and so it is written in Sefer Toldot Yitzchak and in Sefer Menorat HaMaor, that since everything that happened to the forefathers was a sign for their descendants, therefore they found reason to interpret all these matters of the wells as referring to the three Holy Temples which were called ‘wells of living waters’. Just as there was quarreling over two wells, and the third was called Rechovot [wide spaces], similarly with the First and Second Temples, the nations quarreled with Israel until they destroyed them, but the Third Temple, which will be built speedily in our days, is called Rechovot.

ויחפרו, they dug even deeper than initially in order to supply sufficient water for the livestock.

וימצאו שם באר מים חיים, “they found a well of spring water in that region.” The reason the Torah stresses the origin of this water is that the shepherds of the region had accused Yitzchok’s shepherds of diminishing their own water supply by letting their sheep drink from the water of the נחל, the local stream. The water found by Yitzchok’s shepherds did not originate in that stream, but represented a new and additional water supply. Yitzchok’s herds and flocks did not need to use the locally available sources of water.