Prayers have been answered for organisers of this month's Men’s Convention at Katoomba with Simon Manchester confirmed as replacement for speaker Mark Ashton, who is seriously ill with cancer.

"[Simon] is definitely an answer to prayer," says Richard Earley from Katoomba Christian Convention.

Mr Earley says it wasn't easy finding a high-profile Bible teacher who could complement the other speakers.

Bishop Al Stewart had plans already set in place to preach on Daniel and this program had been widely advertised.

"As Simon preached through Daniel last year at St Thomas' [North Sydney] he is a good fit" we are certain Simon will do a great job of preaching boldly."

Mr Manchester (pictured left with the Rev Ian Powell) last spoke at Men's Convention in 2004.

He will also join former deputy PM John Anderson and NSW Police Commissioner Andrew Scipione, who will reveal the pressures of working as a Christian leader in the public eye, over three weekends from February 20.

Mr Earley also says he is relieved by the understanding shown by ticket-holders to the tragic circumstances that led to Mark Ashton, vicar at the Round Church Cambridge, pulling out of the conference.

In December, Mr Ashton was diagnosed with gall-bladder cancer, with secondaries in his liver. The cancer is "beyond a surgical solution', according to a circular Mr Ashton sent to friends and colleagues.

It is hoped Mr Ashton will send a video message, which will include reflections on his situation.

In the circular Mr Ashton says: "I see this as a sentence of life and not of death, as a beginning and not an end."

Mr Earley said no one had cancelled their Men’s Convention tickets as a result of the change in speaker.

"We ask you to please uphold Mark, his wife Fiona and their three children in your prayers," he says.