Charles Ellicott Commentary 2 Samuel 4:8

"And they brought the head of Ish-bosheth unto David to Hebron, and said to the king, Behold, the head of Ish-bosheth, the son of Saul, thine enemy, who sought thy life; and Jehovah hath avenged my lord the king this day of Saul, and of his seed." — 2 Samuel 4:8 (ASV)

The Lord has avenged. —It is not to be supposed that the murderers pretended a Divine commission for their wicked deed; they only meant to say that, in the providence of God, David was thus avenged on the seed of his cruel persecutor. Yet they stated the fact in the way they thought best calculated to awaken the gratitude of David towards themselves.