And Stewart insists Hearts must now move on from the old regime and focus on the future.
"Everything has happened very quickly but I'm delighted to have got a manager in so quickly to fill the massive void that has obviously been left by Csaba Laszlo," he said.
"Thankfully we have got someone in with a big stature and who will hopefully take things forward.
"I'm disappointed Csaba has gone but as I've said I'm delighted to have got a big manager in so quickly.
"We move forward now - it's unfortunate but that's the way things work in football and I'm sure Csaba Laszlo will understand that as well.
"We have got to focus on moving forward."
Jefferies - who was manager of Hearts between 1995 and 2000 - returned to the helm after Laszlo became the eighth manager given the boot since Vladimir Romanov took control of Hearts almost five years ago.
Stewart said: "One of the most important things in any football club is an element of stability.
"This club has had its fair share of instability in recent years but to get someone in of his stature on a long-term contract is important for the club.
"Jim has a connection with the club and I'm pretty sure the vast majority of the fans will be pleased to see the managerial position being filled so quickly with someone with a big name and managerial record like Jim's and a few minds will be put at rest."
He added: "I'd like to think Csaba Laszlo will go on and have a successful career and hopefully get back into football as quickly as possible.
"I have no doubt wherever he goes he will be a success."
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Source: Team Talk
Source: Team Talk