The Hoops travel to Russia on Tuesday, hoping to build on their opening group stage 0-0 draw with Benfica.
"They will go into that game after that full of confidence now," Lennon told BBC Scotland in the wake of his team's comfortable away victory at Fir Park.
"Psychologically, it's important. It's six games in with a game in hand. It was important we went top of the league today. People will be looking up at us now and that is important for the team and the club."
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"We were brilliant from start to finish," Lennon added.
"It should have been a lot more, but I'm delighted at the way we played.
"We defended well and, certainly, some of our attacking play was excellent. We could have made the game a lot more comfortable, but it was one-way traffic more or less.
"Once we adjusted to their system a wee bit, we were superb. Our front three, their movement, the midfield three were great and I have to say I was very impressed with the back four."