John Calvin on Genesis 14:15-16

15. And he divided himself against them . Some explain the words to mean that Abram alone, with his domestic troops, rushed upon the enemy. Others, that he and his three confederates divided their bands, in order to strike greater terror into the foe. A third class suppose the phrase to be a Hebraism, for making an irruption into the midst of the enemy. I rather embrace the second exposition; namely, that he invaded the enemy on different sides, and suddenly inspired them with terror. For the circumstance of time favors this view, because he attacked them by night. And although examples of similar bravery occur in profane history; yet it ought to be ascribed to the faith of Abram, that with a small band, he dared to assail a numerous army elated with victory. But that he came off conqueror with little trouble, and with intrepidity pursued those who far exceeded him in number, we must ascribe to the favor of God.