The Belgium international is proving a bargain buy at £8million with his performances since his summer move from Genk.
Villa have offloaded key players such as Gareth Barry, James Milner, Ashley Young and Stewart Downing in recent seasons.
There has been speculation that Benteke could become a target for one of the leading Premier League clubs during the January transfer window.
But Lambert said: "There's no point in us even being here if it's a case of bringing people in and then letting them go.
"What's the point in that? We're trying to build something here which can take a few years and you need good players with you to achieve that.
"There's no point in them coming for half a season or a year and then we let them go. That's not the right way."
Lambert will look to strengthen his squad next month.
When asked if he will look to sign a couple of players in January, Lambert said: "That's the plan, to look at that. I will talk and see what we have.
"I don't think you stand still. I think you've got to look to improve."
Benteke has been drawing comparisons with former Chelsea star Drogba with his physique and power and the way he tormented the Liverpool defence during last weekend's 3-1 win at Anfield, But Lambert was keen to play down the suggestions.
"I can understand why people are comparing with Drogba with the size of the two guys - but Christian is his own man," he added.
"It's unfair for me to turn around and say he's going to be the next Didier Drogba with the career he's had.
"Christian has only just turned 22. But the potential there is incredible, what he can achieve.