Genesis 14:13-14

13A man who had escaped came and reported this to Abram the Hebrew. Now Abram was living near the great trees of Mamre the Amorite, a brother Or a relative; or an ally of Eshkol and Aner, all of whom were allied with Abram. 14When Abram heard that his relative had been taken captive, he called out the 318 trained men born in his household and went in pursuit as far as Dan.