Genesis 26:20

And the shepherds of Gerar contended with Izhak's shepherds, saying, The water is ours. And it was the will of Heaven, and it dried. But when they returned to Izhak, it flowed. And he called the name of the well (Esek) Contention, because (etheseku) they had quarrelled with him on account of it.

AND HE CALLED THE NAME OF THE WELL ESEK. Scripture gives a lengthy account of the matter of the wells when in the literal interpretation of the story there would seem to be no benefit nor any great honor to Isaac in that he and his father did the identical thing. However, there is a hidden matter involved here since Scripture’s purpose is to make known a future matter. A well of living water alludes to the House of G-d which the children of Isaac will build. This is why Scripture mentions a well of living waters, even as it says, A fountain of living waters, the Eternal., which is the house of the Eternal. He called the first well Esek (Contention), which is an allusion to the First House, concerning which the nations contended with us and instigated quarrels and wars with us until they destroyed it. The second well he called Sitnah (Enmity), a name harsher than the first. This alludes to the Second House, which has indeed been referred to by this very name, in the beginning of his reign, they wrote ‘sitnah’ appears in connection with the Second Sanctuary. against the inhabitants of Judah and Jerusalem. And during its entire existence they were a source of enmity unto us until they destroyed it and drove us from it into bitter exile. The third well he called Rechovoth (Spacious). This is a reference to the Future House, which will be speedily built in our days, and it will be done without quarrel and feud, and G-d will enlarge our borders, even as it says, And if the Eternal thy G-d enlarge thy border, as He hath sworn, etc., which refers to the future. And concerning the Third House of the future it is written, Broader, from the same root as the name of the third well, Rechovoth. The connection between the third well and the Third Temple of the future, concerning which Ezekiel prophesied, is thus established. and winding about higher and higher. [The concluding statement in the present narrative, concerning the naming of the third well], And we shall be fruitful in the land, signifies that all peoples will come to worship G-d with one consent.

ויריבו לנו המים, as we explained in connection with Avraham and Avimelech (21,25), the quarrel was if the source of the water was part of the region of Gerar or part of the region of Beer Sheva. The old quarrel resurfaced now between the shepherds of Yitzchok and those of Gerar.

ויקרא שם הבאר עשק, He gave it a name so that in the future when he would become more powerful than they, the shepherds of Gerar would not be able to claim the well as theirs without protest. The very name already foreshadowed that the claim to this well would be disputed. The meaning of the name עשק as describing dispute is known to us from our sages in Baba Kama 9 המוכר את השדה ויצאו עליה עשיקין, “if someone sells a field and a quarrel ensues concerning it.”