What does 2 Samuel 21:17 mean?

But Abishai, son of Zeruiah, came to David's rescue and killed the Philistine. After that, David's men insisted he not go out to battle anymore, so Israel's light wouldn't be extinguished. 2 Samuel 21:17 - Modern Text Bible

(Abishai saves David, and his men realize David is too important to risk in battle.)