The West Midlands outfit have failed to win any of their last six Premier League games and have also been knocked out of both domestic cup competitions during that run.
Lambert has insisted that he will not quit Villa Park and despite granting the Scot support, Lerner has admitted that things can change quickly in football.
"In the time I've come to know Paul, what is clear is his strength of character and belief in his approach to football," said Lerner.
"Fortunes can shift quickly in this game and a sense that one has it right can become grave doubt in a matter of a few games."
Lerner reportedly revealed to Lambert on Monday that he will not be given significant money to improve his squad in the closing days of the January transfer window.