The former Deputy First Minister has been appointed as the next appraiser of the General Assembly of the Church of Scotland.
Lord Wallace, a senior and member of St. Magnus Cathedral in Kirkwall, Orkney, will win the role next May at the exhibition of the right Rev. Dr. Martin.
The 66-year-old Life Pier will hold a 12-month post representing Kirk at home and abroad.
He said: “I am delighted to be asked to accept this role and I am humbled and proud that people have put their trust in me.
“I am excited and fearful about the challenge of the task ahead, to be honest, it had to pinch me that it was really happening.
“Many have a spiritual longing, and the Church must be fast, innovative and imaginative in how it meets that need.”
He added: “But we have seen positive reactions not only through worship.
“Over the past six months, people have redoubled their efforts to get above the plate, out of our way to help each other and vulnerable members of our communities.
“I want to help build the church in the spirit of one’s neighbor’s service.”
Jim Wallace was President of the Scottish Liberal Democrats from 1992 to 2005 and served as Deputy First Minister from 1999 when the Scottish Parliament was formed.
He was the first minister after the death of Donald Dewar in 2000 and the first minister when Henry McLeish resigned in 2001.
The appraiser-designate took his place in the House of Lords in 2007, but will move to unincorporated benches during his tenure in the role.
With the removal of himself from any parliamentary committees and the Liberal Democrat Chowk, Lord Wallace will not take part in the campaign for the Scottish Parliamentary election, which is set to take place as he becomes moderator in May.
Lord Wallace added: “I went into politics to bring about positive change in society, and my motivation is based on my Christian faith.
“An important belief is that if people are to live life to the fullest as Jesus promised, it will have the impact of the society we love.
“People need to have good health, better education, productive employment and a healthier environment.
“My many years of experience in public life as an MP for Orkney and Shetland, and then as Ms. Orkney I hope I will be in a better position when I fulfill the duties of the General Assembly Assessor.”