Oath of Prime Minister

Q. Why Prime Minister of India takes Oath ?

     The Prime Minister's post is given to the Leader of the majority party at n the Lok Sabha (the lower house). Prior to entering the Prime Minister office the leader of majority party and his Cabinet Ministers need to take oaths of office and secrecy.
The Constitution of India does not specify any specific reason for the oath of the Prime Minister of India. But after going through the wordings of the oaths of office and secrecy it seems that the oaths of office and secrecy is a legal and spiritual practice.
In n the oath taking ceremony the Prime minister swears in the name of God that he is committed to maintain the dignity of his office and he shall maintain the sovereignty and integrity of the country in all circumstances.
Traditionally, the oath taking ceremony takes place at Durbar Hall, New Delhi.Till date (February, 2020) four Prime Ministers take oath at the Rastrapati Bhavan's  (President's House) forecourt.