Charles Ellicott Commentary 2 Samuel 3:19

"And Abner also spake in the ears of Benjamin: and Abner went also to speak in the ears of David in Hebron all that seemed good to Israel, and to the whole house of Benjamin." — 2 Samuel 3:19 (ASV)

Spake in the ears of Benjamin. —Special and careful negotiations with the Benjamites were necessary, because they felt bound to their kinsmen of the house of Saul, and had previously enjoyed great advantages from their connection with their sovereign. Abner reported to David at Hebron the result of his negotiations both with Israel generally and with Benjamin in particular.