Benteke scored his 15th Premier League goal of the season last weekend to help Villa earn a vital 3-1 win at Stoke City.
Lambert believes that the Belgian international deserves huge credit for taking on such a big workload in his debut campaign at Villa Park.
He told The Mirror: "Benteke was brilliant for us again against Stoke, he was up there on his own.
"He played for Genk before the season started, he played every game for the national team, and then played for ourselves.
"But he doesn't look tired at all. The big guy has been terrific."
The 22-year-old needs five more goals this season to become Villa's first player to score 20 in a campaign since 1981.