Contradiction with Proverbs 27:1
Proverbs 27:1 cautions against boasting about tomorrow, which contrasts with the continual hope and praise expressed in Psalms 71:14.
Proverbs 27:1: Boast not thyself of to morrow; for thou knowest not what a day may bring forth. [to...: Heb. to morrow day]
Contradiction with Ecclesiastes 9:5
This verse suggests that the living know they will die, implying uncertainty about the future, which contradicts the continual hope in Psalms 71:14.
Ecclesiastes 9:5: For the living know that they shall die: but the dead know not any thing, neither have they any more a reward; for the memory of them is forgotten.