Simplify the following text for a Grade 13 native English-speaking person.
Original: In 1984 , a series of changes in the Pakistan Penal Code sections relating to blasphemy that , in essence , made it illegal for Ahmadis to preach their religion openly as Islam , leading to arrests and prosecutions .
Simplified: In 1984 , a series of changes in the Pakistan Penal Code sections relating to blasphemy were made , which , in essence , made it illegal for Ahmadis to preach their creed , leading to arrests and prosecutions .