Establishment clause is the legal clause which does not permit the law or any constitution to make a ruling upon it. The establishment clause prohibits the Government from making any type of legal framework.
This clause is not responsible to make any official religion and it does not favour the Government and the law-making bodies to implement this law neither they can make this law nor they can take actions that favour one religion from another which could possibly turn towards the ethnic-cleansing which could cause the cultural diversity.
