In the presence of the Holy Bible, she replied, "All this I promise to do... So help me God."
This oath reveals a lot about the origin of classical liberalism in the West. Countries like England have maintained their Christian identity so far, while being inclusive at the same time. The priest Martin Luther helped found Protestant Christianity (or Protestant Reformed Religion). This religious movement aimed to end the corrupt practices of the Catholic Church and bring people closer to God by removing a middleman. Then, pastor John Calvin's work laid the foundation of modern capitalism on which the whole West survives and thrives, as he claimed that people were created by God to contribute, which was only possible through physical work.
Finally, a religious English philosopher John Locke expounded classical liberalism and a moderate form of secularism by improving upon the work of Christian Modernists before him. He quoted the Holy Bible (Mathew, 22:21), “render unto Caesar the things that are Caesar’s and unto God the things that are God’s” to justify the separation of the Church and the State. According to Locke, this verse taught Christians to keep politics and religion apart.
Today, England is a fairly secular state, but you still have to be a Protestant to become a monarch because there is only a Christian religious oath for the said position. Protestant Christianity is also their official religion to symbolise the roots of Classical English Liberalism and their civilisation as a whole. Meanwhile, the Prime Minister can be of any religion, or a non-believer, because there are oaths for every kind of person running for that office. Something similar was done in Pakistan’s 1956’s Constitution, long after Jinnah’s departure in 1948. The President had to be a Muslim, while the Prime Minister could be of any religion. However, unlike England, Pakistan had no official or state religion until 1973. Islamic religious oaths were made mandatory in 1973’s Constitution for the Prime Minister; so, only a Muslim could become a Prime Minister after that.
A year later, the second amendment defined what it meant to be a Muslim. Now, in oaths, you had to swear that you believed in the finality of Prophet Muhammad (PBUH), which excluded Ahmadis from the race for the Prime Minister's office. Whatever happened afterwards was the chain reaction caused by the new oaths in 1973-74. In simple words, oaths define what kind of state a person is living in. So, this turned Pakistan from a somewhat inclusive secular state into a slightly religious one.
During PML-N’s third term (2013-2018), a change in the Prime Minister’s oath was spotted, which caused an uproar across the country because ultra-conservatives suspected it to be an attempt to make Ahmadis eligible for the Prime Minister’s office again. Hence, the oath was restored to its previous version.
Western secular states of today have two types of oaths. Religious oaths for the believers end with “so help me God.” Believers also swear in the presence of the Holy Book. For example: On the 20th of January 2021, Joe Biden, an American Christian, placed his hand on the Bible and swore a presidential oath which ended with “so help me God.” Meanwhile, non-believers affirm an oath without the Holy Book and references to God. Back in 1947, Jawaharlal Nehru, an atheist, affirmed an oath as the Prime Minister, while Lord Mountbatten, a Christian, swore an oath as the Governor General of Hindustan. There were oaths for all believers as well as non-believers in Hindustan, just like in modern secular states.
In Pakistan, however, Jinnah, who was inspired by English Liberalism, went a bit further and got religious oaths removed entirely. Even if you were a Muslim, you still had to affirm an oath like a non-believer. Jinnah considered it unnecessary for a political leader to put his religion on display, even during an oath. The only thing that mattered to him was the person’s competence. On Jinnah’s request, the Earl of Listowel received a letter on the morning of the 10th of August 1947. The letter was written to make some changes to the oaths.
It read, "Following is form of combined oaths of Allegiance and Office for Governor-General suggested by Jinnah which he hopes will be acceptable... 'I, Muhammad Ali Jinnah, do solemnly affirm true faith and allegiance to the Constitution of Pakistan as by law established...' Only alterations suggested by Jinnah for Governors and Ministers in oaths of Allegiance and Office and Secrecy, substitution of 'solemnly affirm' for 'swear' and omission of words 'so help me God'... I propose to keep to forms already agreed for India."
Hence, both Jinnah and Liaquat Ali Khan (Muslims) affirmed oaths as the Governor General and the Prime Minister of Pakistan by merely holding a paper – which would be the same process for atheists or those of any other persuasion. Jinnah also blocked attempts to declare a state religion and refused to create a ministry of religious affairs. Even Atatürk, who was inspired by the French Revolution’s radical form of secularism, was forced by ultra-conservatives to declare Islam as a state religion in the early years, before removing it later on, once the society arrived at a point where this was possible. Even then, he kept the ministry of religious affairs intact. None of that took place in Jinnah's presence. Meanwhile, two people who were appointed to write the Constitution of Pakistan were Christian and Hindu.
The standard set by Jinnah's secularism in 1947 is still not common, even in the West. Let alone today’s Pakistan.