The winger made his first appearance since December in Sunday's Scottish Cup win over Raith Rovers and will face Inverness this weekend.
And while Lennon admits he should ease the 21-year-old back he is desperate to have him available for the Champions League last-16 clash on Tuesday.
He told the Celtic View: "James is a brilliant player. You can see what he brings to us and he's desperate to play.
"We just need to drip-feed him in now gently and we have to be careful there's no reaction.
"He's a wonderful talent and one of the best Scottish players we've produced for a long, long time. I think the world of him as a boy but as a footballer there's so much he can offer.
"He's been training great and desperate to get back in but the physios have been holding him back. We've had to listen to them but it was great to get him some game time.
"We have the game up in Inverness next and we expect him to play and have him ready for Juventus.
"It was hugely important to get him some game time on Sunday. He makes us better, he drives everyone on, he excites people and got his goal.
"There are not many people who would score that goal - his turn of pace and quality of the finish was fantastic. To have him back gives us an extra dimension."