Mr Gandhi, who is Congress vice president and the Lok Sabha MP from Amethi, was seated in the ninth row along with party colleagues Asrar-ul Haq and Shashi Tharoor.
"Which bench he (Rahul Gandhi) occupies in the future or what role he plays in the next five years is an issue that's purely speculative. I can assure you that he will play a proactive role in tackling a host of issues," said Mr Tharoor.
Those occupying the front benches on the opposition side included Leader of Congress in the House Mallikarjun Kharge, Congress president Sonia Gandhi, M Veerappa Moily and K H Muniyappa.
Interestingly, on the opposite side, another Gandhi sat in a rear row - BJP leader Varun Gandhi, who is the MP from Sultanpur, which is adjacent to Amethi.
The Congress has only 44 members in the 16th Lok Sabha, down from 206 in the 15th, and occupies much less of the opposition benches than the BJP did till the last session. The Congress sat in the Treasury benches to the right of the Speaker for the last 10 years.
Former union minister Mallikarjun Kharge was nominated as the Congress' leader in the Lok Sabha after both Sonia and Rahul Gandhi refused to do so.
It is not yet clear whether he will also be the Leader of the Opposition in the Lok Sabha. For any party to claim that position, Lok Sabha Secretariat sources say, it needs to have at least a tenth of the total strength of the House.
The total strength of the Lok Sabha is 543, so to have a Leader of Opposition a party needs at least 55 seats, which it the Congress does not have.