The defender left the ball after hearing Forster shout for it, allowing Tim Clancy to nip in, round the keeper and stroke the ball into the net for Hibs' first equaliser in an SPL match that ended 2-2.
Lustig claimed that Forster held his hands up after the game to take responsibility for the error and the Swede is adamant that such a mishap is a one-off.
"We chatted about it and sorted it out," he said. "I heard Fraser shout for it so I left it.
"It is one of these things that can happen and while we were both angry and disappointed, it is something that I don't think we can worry about.
"It won't be repeated, that's for sure.
"I am more comfortable at right-back than I am in the middle, but it is something that I need to think about and make sure never happens again."
Lustig will head off now on international duty and he believes that sometimes the break from domestic football can be a chance for players to take a breather as they cope with the pressure and intensity of club football.
"I feel as though the season has just started and that is us breaking up again, but that can be a good thing too because you do come back a little bit refreshed when you are away from it," he said.
"But I am one of those players who doesn't like leaving on the back of a result like that.
"When you draw a game here at Celtic it is never good and ideally I'd have liked to get it out of my system as quickly as possible.
"We can't afford to make the same mistakes that we did against Hibs again. It's important we cut out those kind of errors."
It was not all doom and gloom for Lustig. The player claimed both Celtic goals on Saturday, although their second was officially give as a James McPake own-goal. Boss Neil Lennon later complimented the Swede on his forward play during the course of the afternoon and Lustig insists that he is desperate to grab a few more this term.
"I love to get forward and try to get on the end of things and it was a great feeling to score my first goal for Celtic," he said. "It is good when there are goals coming from all over the pitch.
"My priority, of course, is to stop them going in at the back."