Although some Hoops fans have claimed the banner was a reference to similar protests during the 1993/94 season, plenty of supporters have slammed the message.
Manager Lennon, who will lead his side into their final Europa League group game against Lille on Thursday, branded it “dangerous rhetoric".
Lennon added: “We all want the same thing. The majority of our fans want success.
"The players and everybody here want the same thing. We don't want any divisions. I understand the frustrations and the players are feeling that as well.
"But we don't like that kind of language or expression anywhere near the football stadium. It serves no purpose really.”
The former Hibs boss also discussed the board’s vote of confidence in his abilities.
Lennon continued: “I think it settles everyone down. I know it settles players down for sure. They're really happy about that, thankfully from my point of view. It's full steam ahead. We just need to try to get some consistency and wins now.
"For me there's not an awful lot of work that needs to be done. Just that little bit of confidence, that little bit more of forward thinking.
"We're just feeling a little bit anxious at times on the pitch. I get that. I've been there myself. But they can play through it and that's the one thing they have to do.
"We're hoping we can go out tomorrow and put in a performance against Lille and then take it from there.”