Modi, who came in barely minutes before the proceedings began for the day, went around the front rows greeting leaders with folded hands. (Agencies)
As he neared the Congress benches, Congress president Sonia Gandhi walked into the house and the two leaders exchanged greetings briefly.
Modi, whose act of bowing his forehead and touching the steps of parliament May 20 before his election as BJP parliamentary party leader was widely noticed and commented upon, sought to reach out to the opposition on Wednesday through his gestures.
He occupied his seat on the treasury benches in his new role as the Prime Minister and leader of BJP parliamentary party after greeting opposition leaders, including Mallikarjun Kharge and Samajwadi Party chief Mulayam Singh Yadav.
Earlier, BJP and NDA members stood up and some even thumped their desks as Modi entered the Lok Sabha. As he went along the front rows, more members stood up in their seats.
The mood of the house was subdued due to death of rural development minister Gopinath Munde in a road accident on Tuesday. However, there was also a sense of anticipation and expectation.
The 16th Lok Sabha has 315 first-time MPs in a house of 543 elected MPs, the highest for any house in the last 30 years, according to data compiled by PRS Legislative, a research body that tracks the working of parliament.
The new house also reflected the new reality -- of BJP and NDA's ascendance and Congress decimation in the polls.
With only 44 members, the Congress strength is less than a fourth of its numbers in the last house.
As the proceedings began, BJP members appeared to be present in full strength but there were a few empty seats on the opposition benches.
The visitors' gallery had only a few occupants as oath-taking of new members had been deferred by a day due to the death of rural development minister and BJP leader Gopinath Munde in a car accident on Tuesday.
BJP members felt an acute sense of loss over Munde's demise but also had a sense of elation over the party's first-ever full majority in the Lok Sabha.
"So many BJP members have been elected for the first time. This is a matter of happiness," senior party leader Murli Manohar Joshi said.
Party MP Giriraj Singh said it was a day of happiness but there was pain in the heart over Munde's death.
"The mood would have been celebratory if he was there. Today it is not the same situation," he said.
Former union minister BC Khanduri said it was nice to see treasury benches full of members of the BJP-led National Democratic Alliance.
"The other side had sparse numbers," he said referring to the Congress.
Congress MP and former union minister Shashi Tharoor said the members were all conscious of the tragedy of Munde's demise.
"The first day has a special atmosphere. There were many familiar faces. There are over 300 first-time MPs who were looking around with awe and were also looking around for guidance," Tharoor said.
Tharoor said that having been elected to the house for the second time, he had a school-like feeling of being a senior.
"It was certainly an unusual experience," Tharoor said.
Former Nagaland chief minister Neiphiu Rio said the mood in the house was melancholic. He said the NDA has got a massive mandate and the new government will be more decisive in taking steps for the betterment of the country.
Tarun Vijay, a BJP MP in the Rajya Sabha who was in the visitors' gallery, said the members had a feeling of sadness and the mood in the house was sombre.
Vijay said he had come to witness Modi taking his seat on the treasury benches "which were filled with BJP members".
"I came to see him occupy the seat. It is a lifetime memory for me," Vijay said.
After the house observed silence in the memory of Munde and was adjourned for the day, members greeted each other with namaste, handshakes and embraces. Modi also mingled with members after it was adjourned.
He accepted their greetings and held hands of a few party MPs. Some members bowed to pay him respect.
Senior party leader L.K. Advani spent considerable time meeting members. He went to Kharge's seat and exchanged greetings.
Advani was seated next to Modi. Others in the front row of the treasury benches included Murli Manohar Joshi, M. Venkaiah Naidu, Sushma Swaraj, Rajnath Singh and Lok Janshakti Party chief Ram Vilas Paswan. Kharge, Sonia Gandhi, and former union ministers M. Veerappa Moily and K.H. Muniyappa were among those in the front row of the Congress benches.
Congress vice-president Rahul Gandhi also came to the newly-elected house on its first sitting.
Modi, who came in barely minutes before the proceedings began for the day, went around the front rows greeting leaders with folded hands.