2 Samuel 19:27
And he hath slandered thy servant unto my lord the king; but my lord the king is as an angel of God: do therefore what is good in thine eyes.
Cross-reference
In 2 Samuel 19:17, Ziba crosses the Jordan with David — the same figure Mephibosheth is now accusing of slander in this scene.
In 2 Samuel 14:17, the woman of Tekoa uses the same phrase 'like an angel of God' to describe David's discernment — the exact compliment Mephibosheth repeats here.
In 2 Samuel 14:20, David is again called wise 'as the angel of God' — reinforcing the same analogy for his discernment used by Mephibosheth.
2 Samuel 16:3 records Ziba's false accusation against Mephibosheth; here Mephibosheth refers to that slander.
In 2 Samuel 9:2, Ziba is first introduced as Saul's servant — providing the backstory for the servant who later slanders Mephibosheth.
Exodus 20:16 forbids bearing false witness; here Ziba does exactly that against Mephibosheth.
In 1 Samuel 29:9, the Philistine king Achish also calls David 'as an angel of God' — a repeated honorific used even by Israel's enemies.
Psalm 15:3 describes the righteous as not slandering; Ziba's slander contrasts with that ideal.
Psalm 101:5 says God will destroy slanderers; here Mephibosheth accuses Ziba of slander.
Jeremiah 9:4 warns that every neighbor goes about as a slanderer; this matches Ziba's deception of Mephibosheth.
Proverbs 30:10 warns against slandering a servant to his master — exactly what Ziba did to Mephibosheth, as Mephibosheth claims here.
Exodus 23:1 forbids spreading false reports — the very sin Mephibosheth accuses Ziba of committing against him to the king.
Ephesians 4:31 lists slander as something believers must put away — showing the same sin Mephibosheth says Ziba committed is condemned in the NT.