'Certainly' in the Bible

But David vowed again, saying “Your father certainly knows that I have found favor in your sight, and he has said, ‘Do not let Jonathan know this, or he will be worried.’ But truly as the Lord lives and as your soul lives, there is hardly a step between me and death.”

Please forgive the transgression of your maidservant; for the Lord will certainly make my lord a secure and enduring house, because my lord is fighting the battles of the Lord, and evil will not be found in you all your days.