He is the One Who has placed you as successors on earth and elevated some of you in rank over others, so He may test you with what He has given you. Surely your Lord is swift in punishment, but He is certainly All-Forgiving, Most Merciful.
Meaning:
successor:a person or thing that succeeds another, someone who takes a job or position previously held by someone else.
Elevated: raised, high or important, greater than is normal.
swift: happening quickly or promptly (promptly meaning: at exactly a specified time; punctually).