"We should go on the plank of development to neutralise the Hindutva argument. I would ask everyone in this hall are you better off than four years ago when BJP came to power or not," he said.
"If your answer is no then rather than being vulnerable to the argument if you are good Hindus then vote for us (in 2019)," Mr Tharoor said.
The Congress lawmaker said there are many people who are more Hindus than these people (Hindutva preachers) and claimed that they are not planning to vote for BJP.
"Our agenda is to assess the government on performance," he said.
To a question by the moderator, Mr Tharoor, the author of 'Why I am a Hindu' said, "The lynching of a number of people in the name of cow protection were terrible crimes, because these crimes were conducted. Some of them say these crimes are for Hindutva. Me being a Hindu protest against this. Actually what they are doing by naming this as Hindutva is betraying Hinduism."
Mr Tharoor said the principles of Indian Constitution were based on equality, non-discrimination.
"While our Prime Minister hails the Constitution as holy book, he also hails Deendayal Upadhayaya as guru. But it was Deendayal who thought Constitution was a bad document, imported from west and based on flawed premise," he said.
The Congress MP said about the background of the book, "It took one year plus all the decades of living as a Hindu, thinking about Hinduism reading about Hinduism and interacting with other Hindus and watching with mounting horror what is happening to my faith by advocates of Hindutva."
He said, "With the sense of frustration of being dubbed anti-Hindu by social media trolls, the best thing is to offer a personal testimony."
For the proponents of the ideology of Hindutva, "It happens to be the ideology they believe is the ideology of all Hindu people," which is not.
He said the "book was about liberal inclusive Hindu, someone who claims to be a Hindu and believes inclusive nature of its self."
"It is not the job of a Hindu to teach a Muslim to be Hindu. A Hindu does not look to the holy book, does not look to the heaven. A Hindu looks within himself," he said.