The prolific attacker is desperate to hold on to the runners-up position and hopes to score more goals between now and the end of the season, when he will join Bayern Munich
Last year's Champions League finalists beat Nurnberg 3-0 to leapfrog Bayer Leverkusen in the Bundesliga standings but the Poland international has stressed that they cannot afford to sit back and relax now.
"We are back at second place in the table again and that's what we were aiming for," Lewandowski told the club's official website.
"The season is still long, though. We still have plenty of hard work to do in order to defend our position."
Lewandowski netted once in BVB's win over Nurnberg to take his tally for the season to 15 goals in 23 Bundesliga appearances and he has no intention of slowing down.
"I am very happy with my goal against Nurnberg," he declared. "I want to score many more goals in the remainder of the season."
The 25-year-old will leave Dortmund for Bayern Munich on a free transfer at the end of the season.