In a jibe at Modi, Nitish also recalled a joke which said that while his predecessor Manmohan Singh was accused of not speaking, Modi hardly listens.
Speaking about the growth in social sectors in Bihar, Kumar said, "These things could not have been done merely by talking. If that would have been possible, then there are quite a few top orators in this country. Speaking is one thing and delivering another."
More From This Section
"I heard a joke on WhatsApp that the previous one (Prime Minister) would not speak and the present one would not listen. Nothing happens by talking. You have to do it. And talk only as much as you can do. If you talk more than what you can do, then one day you will be derailed," he said, without naming Modi.
Kumar, who in alliance with Lalu Prasad of RJD is locked in a keen fight with BJP to retain power in poll-bound Bihar, said he always believed talking less than what he could actually do.
The JD(U) leader was also critical of the "collapsed" health care and education sector in the state when he came to power after defeating Prasad-led RJD in 2005 but declined to take any question from journalists on his alliance with his former foe.
Speaking at Bihar development dialogue, which he said was party-neutral and would lay out a vision for what the state should be by 2025, he dismissed views that same party government in the Centre and the state would be good for Bihar, a point made by BJP-led NDA.
He cited the development in the BJP-ruled Madhya Pradesh, Gujarat and Chhattisgarh besides Bihar during the UPA rule at the Centre to make his point.
Nitish's party JD(U) was an NDA ally then and had broken off a 15-year-long association after Modi was named the coalition's prime ministerial candidate.
"Development is the duty of the Centre as well as state. What will happen to the federal structure otherwise?" he said.
In his address, Kumar dwelt at length about the turnaround in the fields of health, education and agriculture during his almost 10-year reign in Bihar.