Genesis 21:34

Many Days. This is more than those days in Hebron, [since] Hebron was 25 years and here it's 26 years. Since he was 75 when he left Haran, the same year (Genesis 13:18) "He came to sit in the tents of Mamre, that beforehand we don't find that he settles in any place other than that, that in every place he goes He was a guest who reside then leaves and goes. As it says (Genesis 12:6) "And Abram passed by," (Genesis 12:8) "And he moved from there," (Genesis 12:10) "And there was a great famine in the land, and Abram went down to Egypt." And in Egypt he was only there for three months until Pharaoh sent him away, from (Genesis 13:3) "and he went on his journey," until (13:8) "he came and sat at the tents of Mamre in Hebron." There he remained until the destruction of S'dom, [and] immediately [afterward] (Genesis 20:1) "And Moses travled from there because of Lot's embarrassment and came to the land of the Phillistines." And then he was 99 years old, that on the third day of his circumcision the angels came to him, that this was twenty five years and thus it is written "many days," [i.e.] more than the first set. And the text does not come to limit [the understanding] but to expand it -- and if you would increase [the years] to more than two or more [than the time he spent in Hebron], it would have been explained. But you don't need this [explatation] when you do not have more than a year, that is to say 26 years. Immediately afterward he'd go and return to Hebron, and it was the same year right before the Binding of Isaac [when he was] 12 years. Thus, it was taught in "Seder Olam" (Chapter 1).