After the akeida it says that Avraham returned to his lads - וישובו אל נעריו.
This can also be translated "he returned to his youth". Avraham saw how Yitzchak was just as happy as Avraham was that he was about to be sacrificed, even though Yitzchak hadn't heard the command directly from Hashem as Avraham did. וילכו שניהם יחדיו - They were equally excited.
Where, thought Avraham, did Yitzchak get this attitude from? It must be his youthfulness.
So Avraham renewed and reJEWvenated himself. וישב אל נעריו - He returned to his state of youth.
[The Heilige Kotzker]
לזכות רבי אפרים אבא בן מרים שושנה לברכה והצלחה בכל מעשי ידיו הוא ביתו וכל אשר לו
