'Assurance' in the Bible

Seeing that many have attempted to draw up a narrative of the facts which are received with full assurance among us

For what assurance have you, O woman, as to whether you will save your husband? Or what assurance have you, O man, as to whether you will save your wife?

Now faith is a well-grounded assurance of that for which we hope, and a conviction of the reality of things which we do not see.