'Certainly' in the Bible

David said to him, "Don't be afraid, because I will certainly extend kindness to you for the sake of Jonathan your father. You will be a regular guest at my table."

Nonetheless, because you have treated the Lord with such contempt in this matter, the son who has been born to you will certainly die."

Certainly we must die, and are like water spilled on the ground that cannot be gathered up again. But God does not take away life; instead he devises ways for the banished to be restored.