Simplify the following text for a Grade 12 native English-speaking person.
Original: Eschatology is literally understood as the last things or ultimate things and in Muslim theology , eschatology refers to the end of this world and what will happen in the next world or hereafter .
Simplified: Eschatology is literally understood as the last things or ultimate things and in Muslim theology , eschatology refers to the end of this world and what will happen in the next world .