וַיַּ֞רְא וְהִנֵּ֧ה בְאֵ֣ר בַּשָּׂדֶ֗ה וְהִנֵּה־שָׁ֞ם שְׁלֹשָׁ֤ה עֶדְרֵי־צֹאן֙ רֹבְצִ֣ים עָלֶ֔יהָ כִּ֚י מִן־הַבְּאֵ֣ר הַהִ֔וא יַשְׁק֖וּ הָעֲדָרִ֑ים וְהָאֶ֥בֶן גְּדֹלָ֖ה עַל־פִּ֥י הַבְּאֵֽר׃
Lalu ia melihat, dan tampaklah sebuah sumur di padang, dan di sana ada tiga kawanan kambing domba berbaring di dekatnya, sebab dari sumur itulah kawanan-kawanan itu diberi minum; dan batu di atas mulut sumur itu besar.
Or HaChaim
חפרוה שרים, which the princes dug. Bereshit Rabbah 64, states that by means of Torah study man is able to make repairs to celestial sources called באר, "well." The extent of the "repair" achieved depends on the depth of the Torah study by the individuals concerned and the spiritual level of those scholars. The Patriarchs who were on a very exalted spiritual level dug this "well," and made its waters fit to drink. This is the mystical dimension of Genesis 29,10 והאבן גדולה על פי הבאר, ויגל את האבן העל פי הבאר וישק את הצאן. "The stone was large on the mouth of the well, and he (Jacob) rolled the stone from the mouth of the well and watered the flocks." From that moment on the Torah was fit to be given to the people of Israel although the stage had not yet been reached where Israel could drink from it. This stage was not reached until Moses "dug" in it, i.e. brought it down to the Jewish people from Mount Sinai. The שרים in our verse are the Patriarchs, the נדבי העם is a reference to Moses. Subsequently the Torah was handed from generation to generation through the elders, the prophets, and eventually, through the Men of the Great Assembly. These people explained the Torah and its secrets. The meaning of the words כרוה נדיבי העם is that if we have only the written Torah without the oral Torah we cannot drink from the Torah's waters.