The young Belgian is still miles from his peak, reckons the Villa boss.
"Benteke is only 21 and can be anything in his career," Lambert said. "He may not hit his peak until 28, you just don't know, but he has been incredible for us.
"You can't compare him because everybody is an individual. He will be his own player, whatever he is going to do in his career.
"For me, looking at him now, he may not hit his peak until later on but he is fantastic and playing in an unbelievable Belgian side.
"He has to keep learning but he is really popular at the football club. That guy has been absolutely colossal for us.
"We watched him before we signed him and I spoke to a few people and they gave a glowing report about him, not just as a footballer but as a guy, which is important. We kept persevering and eventually it happened."