Very Revd Sandy McDonald has revealed he is terminally ill with pulmonary fibrosis.
He served as the Church's Moderator between 1997 and 1998 and was also a presenter for Scottish Television on its religious affairs programme.
His son, David Tennant, is world famous for his role as Dr Who and a more recent part in ITV drama Broadchurch.
Now the clergyman is urging the Church of Scotland to changes its position on assisted suicide and support the proposals.
A bill on the issue is currently progressing through the Scottish Parliament.
Very Revd McDonald, from Paisley, doesn't know how long he has left to live, according to the Edinburgh Evening News.
He said: "I have pulmonary fibrosis. It just gets worse, there is no cure. I have had to address it and decide what to do.
"I have an advance directive which says 'do not resuscitate'. I do not want to be fed by something in my stomach.
"What I do want is the right to a peaceful end to my life.
"I think we have the wrong slant, the wrong emphasis. The phrase - assisted suicide - has criminal overtones in the minds of many people.
"We need to take seriously the provision of a peaceful end of life for all those who need and want it. Of course there would have to be safeguards and that should be discussed.
"We have got so many people in our nursing homes, in our care homes and our bed-blocked hospitals, whether elderly or seriously ill, who are saying 'it's time for me to die'.
"I sympathise hugely with them.
"The doctors and nurses have their hands tied because they are liable to end up in court.
"I believe it is only just that the Church come together and discuss this."
"@davidtennantcom: David Tennant's Dad Tells Of Joy Over National Television Award http://t.co/tqQscY3Yjv pic.twitter.com/GQnqnu63hA" amazing
— DR.WHO NERD! ALLONSY (@pretty_mind2) February 9, 2015