Contradiction with 1 Samuel 26:9
This verse contradicts the idea of harming the Lord's anointed, as David advises against it, while 2 Samuel 4:2 discusses the murder of Ishbosheth, a king.
1 Samuel 26:9: And David said to Abishai, Destroy him not: for who can stretch forth his hand against the LORD'S anointed, and be guiltless?
Contradiction with Exodus 20:13
This verse states "Thou shalt not kill," contradicting the actions of Rechab and Baanah who killed Ishbosheth.
Exodus 20:13: Thou shalt not kill.
Contradiction with Romans 12:19
This verse advises against taking vengeance, which contradicts the implied motives in 2 Samuel 4:2 for Ishbosheth's murder to secure David's favor.
Romans 12:19: Dearly beloved, avenge not yourselves, but [rather] give place unto wrath: for it is written, Vengeance [is] mine; I will repay, saith the Lord.
Contradiction with Matthew 5:44
This verse encourages loving enemies and not harming them, which contradicts the betrayal and murder described in 2 Samuel 4:2.
Matthew 5:44: But I say unto you, Love your enemies, bless them that curse you, do good to them that hate you, and pray for them which despitefully use you, and persecute you;
Contradiction with Proverbs 6:16-17
These verses list actions God hates, including the shedding of innocent blood, contradicting the murder in 2 Samuel 4:2.
Proverbs 6:16-17: These six [things] doth the LORD hate: yea, seven [are] an abomination unto him: [unto...: Heb. of his soul]