Benteke has missed Villa's last three games due to a knee problem but trained on Monday ahead of the trip to Wearside.
The Belgium striker scored 23 times during a stand-out debut campaign in English football last year but has struggled for form this season.
He has scored just five goals - the last of which came in the 2-1 home defeat by Newcastle three months ago.
Lambert said: "Christian trained on Monday morning and looked okay. He feels okay within himself. The thing with Christian is he's a young guy, and people forget that.
"Everyone put this super-stardom thing on him, but he's 23 years of age.
"He's a young guy and his confidence suffers, as everyone else's does. He's back and hopefully he will do what he did at the tail-end of last season.
"This is the point where Christian scored all his goals and if he does all that, it would be great."
Villa captain and defender Ron Vlaar, who has been out for five games due to a calf injury, did some light training on Monday morning and may also make his comeback at the Stadium of Light.
Villa have lost four of their last five games but Lambert insists there is still plenty of grounds for optimism.
"We are only three points off 10th so it is not doom or gloom," Lambert said. "It's how people want to portray it. I've never been a negative person."
"If you look at the table, we are sitting in a pretty decent position. We are ahead of where we were last year.
"Ideally, we want to play better, there's no two ways about it, but it was important we stopped the sequence (of four successive defeats) on Saturday - that was absolutely paramount, that we stopped our losing run.
"We have to have everyone fit, and hopefully one or two are coming back. We are three points behind 10th, which is incredible.
"The great thing about the Swansea game was after Boxing Day (when Villa lost 1-0 at home to Crystal Palace) they came out and a young side did not capitulate.
"They kept going and had a great desire not to get beat. If you can't win it, it is important not to lose it."