The Scottish champions host the Italian giants in the Round of 16 first leg at Parkhead and the manager has urged his charges that they really have to make the most of the opportunity that lies in front of them.
"To qualify was the best thing I've done in a managerial sense - to get out of the group with 10 points," Lennon said.
"We might never get this opportunity again. I don't want people thinking this is going to be an annual thing, because it's a very difficult thing to do. So we have to maximise our opportunities.
"We might never get here again. Gordon Strachan did it two years in a row here, Alex McLeish did it [with Rangers] the year before that. So it was almost as if it was going to be a foregone conclusion every year. But it's such a difficult ride to get here. We have to make the most of it now.
"We have to enjoy these moments and enjoy these nights. We have given the fans something to believe again, something to dream about. That's been missing for a long time."
But Lennon was also quick to caution Juventus who would be fancying their chances: "It would be dangerous to underestimate Celtic. We have proved in the Champions League that we can be a match for anyone."