Contradiction with 2 Samuel 6:16
This verse implies Michal was critical of David, contrasting the love mentioned in 1 Samuel 18:20.
2 Samuel 6:16: And as the ark of the LORD came into the city of David, Michal Saul's daughter looked through a window, and saw king David leaping and dancing before the LORD; and she despised him in her heart.
Contradiction with 2 Samuel 3:13-16
These verses suggest Michal's affections were elsewhere, contradicting any implication of lasting love in 1 Samuel 18:20.
2 Samuel 3:13-16: And he said, Well; I will make a league with thee: but one thing I require of thee, that is, Thou shalt not see my face, except thou first bring Michal Saul's daughter, when thou comest to see my face. [that is: Heb. saying]