Second half goals by James Forrest and Odsonne Edouard make the Scottish champions strong favourites to progress to the group stage but Lennon remains cautious.
“You never say it’s enough,” said the Celtic manager. “We have a big [league] game at the weekend [against Hearts] and then we’ll approach the second leg against AIK as professionally as we always do, make sure we can get the job done properly and look forward to the group stage. We still have a very important 90 minutes ahead of us and we can’t take anything for granted.
“It was an outstanding performance from us tonight, a great team performance. We played particularly well in the first half but in the second half had real good control of the game. We could have scored more.
“I’ve got to be delighted with that. All round, everyone was in good nick. Some of the football we played was great and we scored two fabulous goals.”
Lennon heaped praise on French striker Edouard whose stunning free-kick goal set the seal on a fine all-round individual display.
“He is playing brilliantly,” said Lennon. “He is in brilliant goalscoring form and is leading the line superbly. I can’t speak highly enough of his talent and mentality. He is becoming such an integral part and important figure in the team. His goal was absolutely outstanding.”
Lennon was also gratified by the response of the Celtic support after the recent discontent among them following last week’s elimination from the Champions League.
“I have to pay tribute to the supporters tonight, they were fantastic,” he added. “It was a great atmosphere for the players to play in.”
AIK head coach Rikard Norling had no complaints about the result but insists his side are capable of turning the tie around in the second leg.
“We played a good team, Celtic deserved to win,” said Norling. “We handled it quite well in the first half, in the second half we made a mistake when we conceded an early goal which was a tough blow.
“Celtic were the better team but it’s half-time now and we take it back to Stockholm. It’s definitely a big task for us but we won’t hold anything back. We will go with everything we can. We know we will have a great crowd behind us. We are still alive – the tie is not over.”
Celtic paraded Fraser Forster at half-time after completing a deal to bring the goalkeeper back to the club on loan from Southampton.
The 31-year-old, who has made only one appearance for the English Premier League side since Boxing Day 2017, previously spent four seasons at Parkhead before leaving for Southampton five years ago.
Forster is keen to find a way back to first-team football at the club where he made 193 appearances and won three Scottish league titles and two Scottish Cups. Forster said: “I’m absolutely delighted to be here, it feels like I’m coming home and I’m buzzing to be back at this great club. Now, I just want to get back training and get back playing.
“The gaffer [Neil Lennon] has always been brilliant with me, and when the opportunity came up to come back and work with him again, it was one that was too good to turn down.
“I’m delighted to be back. I know a lot of the lads, which is makes it feel like I’ve come back home. “With that in mind, I hope I can fit straight back in,” added Forster on
He will wear the number 67, representing the year club’s Lisbon Lions won the European Cup, after requesting it. “Obviously, I know what the number 67 means to this great club,” he said. “It’s an honour to wear the shirt and an even bigger honour to wear this number. I loved my time here before and I felt like it was the right number for me, I’m really proud to wear it.”