NEW DELHI — On Monday, the swearing-in of the new Indian prime minister began like a mishap. The ceremonial head of state, President Pranab Mukherjee, who administered the oath, said, “I” and looked sideways as though he were about to say, “I really wanted to be prime minister.”

For that was once considered his destiny, and it was almost within his grasp as a powerful leader of the Indian National Congress. But the party chose Manmohan Singh and eventually got rid of Mr. Mukherjee honorably by nominating him as president, which is a bit like the British monarch but without the estate. Mr. Mukherjee, of course, stopped after “I” and looked at Narendra Modi, who then read the oath and assumed office as the head of government.

In an unsung coincidence, the man who administered the oath had contributed in an immeasurable way to the rise of Mr. Modi and his Bharatiya Janata Party. For Mr. Mukherjee was a disaster as finance minister from 2009 to 2012. The relationship between Indian business and the government deteriorated as he presided over a slowing economy, and the Congress party never recovered.

As Mr. Modi and his ministers were sworn in, the news media covered the event with enthusiastic optimism, with television commentators showering compliments on the newborn government, which they said looked a lot like its single parent, Mr. Modi.