"All political parties need to be well trained to sit in opposition. Why is then the Congress scared of sitting in the opposition," Jaitley wrote in his blog, adding the Congress leaders "will do well if they reconcile to their seats in the opposition".
"A stint in the opposition does a lot of good to you when you introspect and plan for the future," he said.
Jaitley also said the Congress will be reduced to a two digit party
He said the popular mandate is not with the Congress. He also said the Congress will be reduced to a two digit party, indicating the number of seats it will win in the Lok Sabha election.
"The idea of getting out of power is making the Congressmen (Congress leaders) bitter and desperate. The prime minister has become cynical. He complains to people he meets that he has been unfairly targeted. The Gandhis believe that they were God's gifts to India and were meant only to rule," he said.
He pointed out how the Congress frowned at the very idea of a tea vendor defeating them at the polls and ruling India, hinting at BJP's prime ministerial candidate Narendra Modi.
The senior Bharatiya Janata Party leader said the opposition has a powerful role to play in Indian democracy and to safeguard public interest.
He said political power in a democratic system is shared by various players.
"Governments no longer are the sole repository of all powers. Opposition, media, judiciary, bureaucracy, civil society are co-sharers in the power," he said.
"Political positions are not permanent. If the Congressmen (Congress leaders) on the eve of their departure are laying down an agenda of confrontation with the current opposition, they are only laying down an agenda for the future," he said.
"Nobody will accept the argument that what the Congressmen are doing is justice and when the same is reciprocated it is vindictiveness," he added.