Rangers manager Ally McCoist has stood by Ian Black after he was found guilty if illegal betting by the SFA - three times against his own side - and will select him again after he has served his three-game ban.
But when asked if anyone would play for him after committing such an offence, Lennon replied: "It would be very difficult."
Lennon revealed the SPFA recently visited his squad to remind them of the rules and their responsibilities as part of the union's attempt to keep their members out of trouble.
And, he warned he would be very unhappy if he was to discover any of his Bhoys had bet against his own team.
Lennon said: "I would take a very dim view of it. I'm not aware of it among my own players. But it is an unwritten rule you can't do it.
"In all my time as player and a coach, it is a complete no no."
Black has been handed a ban, a suspended sentence and a £7,500 fine for his actions.
And Lennon reckons there is no need to have automatic six or 12-month bans in place to act as a deterrent.
He said: "You have to take each individual case on its merits. The Tribunal will handle it they way they see it. There is a set ban in place and pretty heavy fine as well, so, hopefully, it is a lesson learned."
Lennon us unwilling to get too heavily involved in commenting on this particular case, admitting: "I wasn't present. I don't know all the facts.
"I'm not trivialising it, but it might not be as bad as we are all making it out to be.
"Because I wasn't there at the Tribunal, I don't know the merits of the individual case."
He added: "Look, it has been going on since the prehistoric age. We all like a punt now and again. The rules are there, and if you cross the line, you expect to be punished."