Contradiction with Job 14:4
Job 14:4 suggests that no one can bring a clean thing out of an unclean, indicating the innate impurity of humans, which contrasts with Psalms 51:7’s idea of being purified.
Job 14:4: Who can bring a clean [thing] out of an unclean? not one. [can...: Heb. will give]
Contradiction with Ecclesiastes 7:20
Ecclesiastes 7:20 states that there is not a just man on earth who does good and does not sin, implying perpetual impurity, which contradicts the notion of being cleansed in Psalms 51:7.
Ecclesiastes 7:20: For [there is] not a just man upon earth, that doeth good, and sinneth not.