'Certainly' in the Bible

Certainly no one will remember the wise man or the fool in {future generations}. When [future] days come, both will have been forgotten already. How [is it that] the wise man dies the same as the fool?

There is certainly no righteous man on the earthwho does good and never sins.

For man certainly does not know his time: like fish caught in a cruel net or like birds caught in a trap, so people are trapped in an evil time as it suddenly falls on them.