Job 2 Satan’s Second Accusation

How is this similar to the first time Satan appears before God?  How is it different?  What does Satan want to do?  Why did he have to get “permission”?  Why did God give the permission?  How important is “integrity”?  Even Job’s wife… why is this so important in this story?  And the three “friends”… say nothing for 7 days and 7 nights?  Could we do that?