Contradiction with Jonah 2:6
This verse describes Jonah's descent but emphasizes God's delivering power, contrasting with David's humility and acceptance of his low status in 1 Samuel 18:18.
Jonah 2:6: I went down to the bottoms of the mountains; the earth with her bars [was] about me for ever: yet hast thou brought up my life from corruption, O LORD my God. [bottoms: Heb. cuttings off] [corruption: or, the pit]
Contradiction with Matthew 23:12
This verse states that those who humble themselves will be exalted, which indirectly contrasts with David's humility because David considers himself unworthy rather than seeking eventual exaltation.
Matthew 23:12: And whosoever shall exalt himself shall be abased; and he that shall humble himself shall be exalted.
Contradiction with Luke 14:11
Similar to Matthew 23:12, it suggests a future exaltation for the humble that is not explicitly acknowledged in David's reasoning in 1 Samuel 18:18.
Luke 14:11: For whosoever exalteth himself shall be abased; and he that humbleth himself shall be exalted.