His father worked for the Northern Lighthouse Board and, as a child, Morrison lived in various places around Scotland and went to school in Oban, Stromness and Edinburgh.
During the latter period, he served as Moderator of the Free Presbyterian Church's Southern Presbytery.
Within the Church of Scotland he served as the Moderator of the Presbytery of Lewis for the 2003 to 2004 session, Convener of the Mission and Discipleship Council (2005-2009) and Chaplain to the Lord High Commissioner (2005 and 2006).
[1][3] In March 2014, two months ahead of taking up the role, the Church of Scotland announced that Morrison had withdrawn his nomination as Moderator on grounds of ill health,[4] Following this, John Chalmers (Principal Clerk to the General Assembly) was selected to be Moderator ahead of the 2014–15 session.
[5][6] On 28 October 2014 Morrison was again successfully nominated to be Moderator of the General Assembly of the Church of Scotland, for 2015–16.