The 21-year-old closed down his Twitter account soon after joining Aberdeen on loan from Celtic on Tuesday night, after a foul-mouthed tweet emerged from 2012.
Written while he was an Inverness youth-team player, Christie posted: “I f****** hate Aberdeen #sheeps*******c****.”
After arriving at Pittodrie, Christie told several newspapers: “It looks bad but when I tweeted it I was very young. I can’t even remember tweeting it to be honest.
“When I was growing up in Inverness there was a rivalry with Aberdeen and I would have been winding up my Aberdeen-supporting mates.
“Looking at it now, I apologise to anyone who has taken offence. But I hope nobody reads too much into it. I was only 17 and my Twitter is long gone now.
“It’s up to me now to win people over. If anyone is annoyed with me, the challenge is to win them back with my performances.”