"They have a young leader who is just learning to give speeches. Since the time he has learnt to speak, there is no limit to my happiness. In 2009, you couldn't even tell what is inside this packet and what is not. Now we are finding out," Modi said without naming Gandhi.
"He had been going around threatening that when he will speak, there will be an earthquake. If he hadn't spoken, there could have been an earthquake. It would have been an earthquake that people would have had to deal with for 10 years.
"There is no chance of an earthquake now that he has spoken. We can be rest assured that there is no danger of the natural calamity in sight," the PM said, a day after Gandhi's accusation against Modi of taking money from Sahara and Birla groups when he was Gujarat Chief Minister.
BJP had rejected the Congress leader's allegations as "baseless, shameful, and mala fide".
Accusing the Government of not allowing his to speak in Parliament, Gandhi had earlier said that "an earthquake will come" if he speaks and had gone on to claim that he had knowledge of "personal corruption" by Modi.
The Prime Minister, who was on his first tour of his Lok Sabha constituency after Rs 500 and Rs 1000 notes were demonetized on November 8, was speaking today at a function organised inside the Banaras Hindu University campus.
He also took potshots at Gandhi's assertion that payments through cards, online transfers etc. would face hurdles in the country due to low literacy levels, saying, "I hope he does not say that I had indulged in some sort of black magic to make illiterate those who knew how to read and write.
"He never thinks before he speaks and he may not have realized that he has admitted the failure of the long reign of his own party," the PM said adding his detractors have been forced "to admit, even if unwittingly, their failures".
He said a cleanliness campaign has been launched and the "stink" raised during cleaning of garbage which is scattered everywhere is the same that the country is feeling now.
Modi said he is happy that note ban has "exposed the 'kala dhan' (black money) as well as 'kale mann' (ill-intentions) of many".
Taking a jibe a former Prime Minister Manmohan Singh, he said poverty is his legacy adding Singh's image is clean but a number of major scams had taken place during his tenure.
Reacting to his predecessor's assertion in Parliament that a cashless economy was not feasible for the country where nearly 50 per cent of people were poor, the Prime Minister said, "I wonder whether he (Singh) was giving his own report card by admitting the dismal situation.
"After all, he has not just been the Prime Minister for two terms and a Finance Minister previously. Since the 1970s he has been holding key positions.