The then Prime Minister delivered the speech to the Church of Scotland’s General Assembly in 1988, causing controversy among some over its theological justification for capitalism and the market economy.
But it is the religious openness in the address which the Right Reverend Dr Derek Browning believes would make it difficult for a politician to recreate today.
Speaking ahead of the General Assembly, and in a personal capacity, he said: “I don’t know if (the speech) could be made the same way today.
“What was really interesting was that Margaret Thatcher was a woman of faith and so she was speaking from her faith perspective.
“We famously remember Alastair Campbell saying to his Prime Minister Tony Blair ‘we don’t do God’.
“I think politicians are sometimes nervous about talking about faith-related matters.”
He added it was “good democracy” and “good politics” for religions to interact with each other, as well as with national and local politicians.
In her address, Mrs Thatcher cited that “Christianity is about spiritual redemption, not social reform”.
It’s nickname comes the Sermon on the Mount and because the Assembly Hall is on Edinburgh’s Mound.
She also emphasised personal responsibility, quoting St Paul by saying: “If a man will not work he shall not eat.”
This was difficult for some in the hall, who believed it went against the Church’s message of “mutual responsibility” across the community.
After the speech, the then Moderator Professor James Whyte gave Mrs Thatcher church reports on poverty, housing and a fair social benefit system.
Aged 25, it was the first time in the hall as a minister for Dr Browning.
He said: “Margaret Thatcher was a controversial individual - she could have been giving a cookery recipe and people would have found it controversial.
“We knew that by having her with us people would be watching and listening intently to what she had to say.
“The General Assembly has a long tradition of bringing challenging people to come and speak.
“The Church of Scotland is not afraid of engaging with people who are strong in their views.
“Sometimes we will agree with what’s being said sometimes we will not agree with what’s being said.
“The important thing is dialogue.”
Mrs Thatcher also talked about there being no place for bigotry in society and that people of all faiths should be made to feel welcome.
This part of the speech “still needs to be heard in our country today”, according to the Right Rev.
The Church of Scotland is to begin its General Assembly on Saturday.
It will see Dr Browning stand down as Moderator and Rev Susan Brown take up the position.