Albert Barnes Commentary 1 Chronicles 11:11

"And this is the number of the mighty men whom David had: Jashobeam, the son of a Hachmonite, the chief of the thirty; he lifted up his spear against three hundred and slew them at one time." — 1 Chronicles 11:11 (ASV)

Chief of the captains - Or, “of the thirty,” according to another and better reading (see 1 Chronicles 11:15, 1 Chronicles 11:25; compare 2 Samuel 23:8 note). Jashobeam was the commander of the first monthly course of 24,090 soldiers (1 Chronicles 27:2). He is probably the warrior of the same name who joined David at Ziklag (1 Chronicles 12:6).