“And you are [Sarah’s] children, if you do good and do not fear anything that is frightening.”
The world is a scary place. It was scary when Peter wrote these words, and it’s scary today. Maybe it’s scariest for women, though I can’t say for sure: there are plenty of places in scripture where men are told not to be fearful, and many exhortations not to let our fears control us which we may reasonably assume are intended to apply to both sexes.
In fact, some of the most powerful men in the Bible were scared.