Passage cross-references.

Then answered David and said to Ahimelech the Hittite, and to Abishai the son of Zeruiah, brother to Joab, saying, Who will go down with me to Saul to the camp? And Abishai said, I will go down with thee.

And there were three sons of Zeruiah there, Joab, and Abishai, and Asahel: and Asahel was as light of foot as a wild roe.

So Joab and Abishai his brother slew Abner, because he had slain their brother Asahel at Gibeon in the battle.

And David sent forth a third part of the people under the hand of Joab, and a third part under the hand of Abishai the son of Zeruiah, Joab’s brother, and a third part under the hand of Ittai the Gittite. And the king said unto the people, I will surely go forth with you myself also.

And David said to Abishai, Now shall Sheba the son of Bichri do us more harm than did Absalom: take thou thy lord’s servants, and pursue after him, lest he get him fenced cities, and escape us.

But Abishai the son of Zeruiah succoured him, and smote the Philistine, and killed him. Then the men of David sware unto him, saying, Thou shalt go no more out with us to battle, that thou quench not the light of Israel.

And Abishai, the brother of Joab, the son of Zeruiah, was chief among three. And he lifted up his spear against three hundred, and slew them, and had the name among three. …

Whose sisters were Zeruiah, and Abigail. And the sons of Zeruiah; Abishai, and Joab, and Asahel, three.