Commentaire sur La Genèse 26:27

ויאמר אליהם יצחק, Issac said to them, etc. We have to understand why Isaac spoke to the king and his entourage in such a hostile manner. It seems incompatible with our image of Isaac. Besides, seeing that in the end he did make a covenant with them, what was the point of the hostile attitude Isaac displayed initially? Furthermore, once Isaac had told Avimelech and company that they hated him, why did he spell out how this hatred had expressed itself, i.e. by his being expelled from Gerar? If the latter sentence was meant to prove the Philistines' hatred of him, he should have said כישלחתם אותי, when you expelled me instead of ותשלחוני מאתכם, suggesting that they let him go unmolested?

ויאמר...ותשלחוני, the plural mode here indicates that at the time when Avimelech had expelled Yitzchok he had done so by following the advice of his ministers and notables. He had also said at that time “לך מעמנו,” Go from us!”

We must understand Isaac's words as reflecting his awareness that the only reason Avimelech displayed any interest in making an agreement with Isaac was his concern that possibly his own inheritance would be in jeopardy due to G'd's promise to Abraham of the whole land of Canaan. Abraham had already reassured Avimelech about those concerns and Isaac his son would certainly not be able to annul a promise made by his father. There was therefore no reason for Avimelech to approach Isaac in this matter. Isaac reasoned as Maimonides rules that vows undertaken with the consent of the other party cannot be revoked except with that party's consent. Since Abraham had not done so during his lifetime it was too late for Isaac to make any changes, anyways (based on Job 37,18). Under the circumstances Avimelech had no need of Isaac at all. When Isaac said: "why did you come?" this is not to be understood as a hostile statement, but as pointing out that there was no need for them to come all the way in order to request what they were about to ask. Seeing this was so, he could only assume that they had come for his sake, presumably in order to lure him back to Gerar. He alluded to this by using the word אלי, to me. This was hard to believe, however, in view of past hostility shown him. He added the word ואתם, and you, referring to Avimelech and his ministers personally; he meant that it was not just the population at large which had displayed hatred towards him. By using the word ותשלחוני, Isaac meant that their hatred of him was based on jealousy. It is a well known fact that hatred may evaporate unless it is caused by jealousy. Hatred based on jealousy will not abate until the cause (Isaac) of the jealousy has disappeared. Isaac challenged Avimelech that their hatred of him would not disappear as it was based on jealousy.