In the spring, at the time when kings march out to war, David sent out Joab and his servants with the whole army of Israel. They destroyed the Ammonites and besieged Rabbah, but David remained in Jerusalem.
Jewish Publication Society of America Version (JPS1917) - 2 Samuel 11:1 >And it came to pass, at the return of the year, at the time when kings go out to battle, that David sent Joab, and his servants with him, and all Israel; and they destroyed the children of Ammon, and besieged Rabbah. But David tarried at Jerusalem.