as Sarah obeyed Abraham, calling him lord, whose children you now are, if you do well, and are not put in fear by any terror.
Calling him lord ...  The significance of Sarah's doing this lies in the fact that this is what she called him in her own heart, not merely when others might hear her.  The real test of what one is, or what one thinks, lies in the content of what they say to themselves, not in what they might say to others  (Genesis 18:12).