'Certainly' in the Bible

“Therefore you are to speak this word to them, ‘Thus says the Lord, the God of Israel, “Every jar should be filled with wine.”’ The people will say to you, ‘Do we not already know that every jar should be filled with wine?’

But rather we will certainly perform every word of the vows we have made: to burn sacrifices to the queen of heaven (Ishtar) and to pour out drink offerings to her, just as we ourselves and our forefathers, our kings and our princes did in the cities of Judah and in the streets of Jerusalem; for [then] we had plenty of food and were prosperous and saw no misfortune.