Agbonlahor scored the only goal of the game as Villa beat Sunderland 1-0 last weekend, and Lambert believes that Agbonlahor can help the club climb up the Premier League table if he keeps up his form.
Lambert said: "I think Gabby at this minute in time is playing extremely well. There is a belief that he's starting to hit top form and is definitely a real handful. He's really quick.
"When he gets up to speed, he is a handful. If he can get goals to go with his game, he will be really fine."
Agbonlahor is expected to start Villa's match with Manchester United on Saturday.