"And he divided himself against them by night, etc." (Genesis 14:15). Abraham made war with them until the middle of the night, and the Holy One, blessed be He, [made war] with the Egyptians from the middle of the night onward, and slew their firstborn. "And he pursued them as far as Hovah" (Genesis 14:15) — he pursued after them as far as the place of the guilt of his sons.
Abraham's Midnight War and the Pursuit to Hovah in Midrash Aggadah
Midrash Aggadah, Genesis 14:15
ויחלק עליהם לילה וגו'. אברהם עשה מלחמה עמהם עד חצי הלילה, והקב"ה עם המצריים מחצי הלילה ואילך, והרג את בכוריהם: וירדפם עד חובה. רדף אחריהם עד מקום חובתן של בניו: