Derry Girls star, Tommy Tiernan, had to ask Ruby Wax "are we fighting?" on the Tommy Tiernan Show on RTE1 on Wednesday evening.
Wax was a guest and was promoting her new book How to Be Human: The Manual.
The book focuses on how the mind works and mindfulness.
Wax, who shot to fame in the 1990s, has gradually withdrawn from public life to concentrate on studying for a Masters degree in Mindfulness at Oxford University.
Tiernan and Wax appeared to clash over the interpretation of the book which resulted in Tiernan asking Wax "are we fighting?".
"Yes we are," replied Wax. "If you'd rather go run through a field than read a book then don't read and go run through a field."
"Why is that a threat to you?" asked Tiernan.
"I'm not threatened, I'm just saying, it's kind of insulting to be honest," said Wax.
In what is the second series of the show, Carndonagh born stand-up comedian Tommy Tiernan and the audience have no idea who the guests will be until they walk out on stage.
As a result, Tiernan can't conduct any research into the people he will be interviewing nor can he have any pre-prepared questions.
In some instances, the guest has had to tell Tiernan who they are before the interview even begins.