1 Chronicles 12:2

They were armed with bows
Much used in war in those times: and could use both the right hand and the left, in hurling stones, and
shooting arrows out of a bow;
they were ambidextrous; who could sling stones, or shoot arrows, with either, which was no small advantage to them: even of Saul's brethren of Benjamin;
they were of the tribe of Benjamin, of which Saul was, and so his brethren; and they might be, at least some of them, his relations and kinsmen; who observing the unreasonableness of Saul's enmity to David, and detesting his cruelty, and sensible of the innocence of David, and of the service he had done his country; and perhaps not being ignorant of his divine right and title to the kingdom, went over to him, to comfort, strengthen, and assist him.