A ledger stone in the central aisle of the nave of the central London church now commemorates him.
The inscribed slab was officially unveiled during a service held at 3pm on Wednesday afternoon.
Theuns Pauw from African Enterprise International - an evangelistic mission - told Premier's Inspirational Breakfast that Mr Mandela made a last impact on his country.
Speaking from South Africa, he said: "I can unequivocally say that Nelson Mandela's legacy is still alive and strong in our nation, and still inspiring hope and change for the good."
A service of thanksgiving for the life of Nelson Mandela was held at the Abbey on 3rd March 2014, following his death on 5th December 2013.
Referring to Mr Mandela's release from prison in 1990, Mr Pauw went on to say: "It was remarkable that he came out of 27 years of incarceration with zero signs of bitterness.
"[It was] absolute spirit of forgiveness, something really Christ-like that he came out with.
"He was seeking to bring reconciliation."
Mr Mandela played in a leading role in trying to overthrow a pro-apartheid government in South Africa, before going on to serve five years as the nation's President (1994-1999).
Urging people to pray for South Africa ahead of national elections next year, Mr Pauw added: "Right now, in our country, we're building up towards our national elections...
"There are a lot of people who are pushing the racist ticket and really polarising the different ethnic groups in our country, so it's a very crucial time for us and we really covet prayer for our country at this time."
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