1 Chronicles 19:15

And when the children of Ammon saw that the Syrians were fled, they likewise fled before Abishai, his brother, and entered into the city, they took refuge behind the strong walls of their capital, Rabbah. Then Joab came to Jerusalem, reserving the capture of the Ammonite capital for a later season. It is an easy matter for the Lord to grant the victory to the weaker side if thereby His plans are promoted.