Rangers fans chief Chris Graham has apologised for sending the "inappropriate" tweet which forced him to resign as a club director after just three days.
The Rangers Supporters Trust spokesman was only handed his blazer on Tuesday.
But the 38-year-old has now been forced to step down after it emerged he sent a tweet featuring an image of the prophet Mohammed engaged in a sex act with Star Wars character Jar Jar Binks.
The image was posted from Graham's account just hours after the Charlie Hebdo attack in Paris. Muslim leaders in Glasgow had demanded the club take action against Graham, while Police Scotland have confirmed they are now investigating the matter.
Graham now admits he should not have not have sent the tweet.
In a personal statement given to Press Association Sport, he said: " Freedom of speech is one of the foundations that our country is built upon. However, with that freedom comes a responsibility to be sensitive to the views of all our nations' communities.
"This tweet did not do that. For that I apologise unreservedly.
"I also tweeted my support for the Muslim community during exchanges that day but even so I accept that retweeting that cartoon was inappropriate.
"I am extremely proud to have played a part in helping Rangers to secure regime change but I have had to take this decision for my family and the club itself.
"I wish the current board the very best of luck going forward."
Graham's departure was announced to the Stock Exchange shortly after 2.30pm on Friday, with a short club statement saying: " Chris Graham has tendered his resignation as a Director of RIFC. This has been accepted by the board."
His short-lived directorship is a major embarrassment for Dave King's new regime just a week after they snatched power with last Friday's general meeting.
King - who has not yet taken up his seat on the board while he sets about proving to the football and City authorities that he is fit and proper - had promised to ensure the club's supporters were represented at director level after they backed his boardroom coup.
Graham was nominated on behalf of the RST, while Rangers First member James Blair has been handed the role of club secretary.
Speaking on Tuesday, interim chairman Paul Murray said: "Chris and James have been appointed in accordance with the board's commitment to meaningful fan representation and in order that they can use their abilities to contribute to the company."
Meanwhile, the Scottish Football Association has announced Rangers' appearance before a j udicial panel disciplinary hearing into Mike Ashley's Ibrox involvement, originally scheduled for Monday, has been postponed "at the request of the club" until Thursday, April 16.
Source: PA
