Speaking publicly for the first time since his release last Monday, Stephen McGown (pictured, second from right) told reporters becoming a Muslim helped him cope with the ordeal.
He said: "Before the desert, I was a Christian. I entered [Islam] of my own accord. I see many good things in Islam. It requires a very good character, a very strict character."
The 42 year old was captured in the west African country's capital Timbuktu in 2011, along with two other men. A fourth was killed during the kidnapping.
Speaking in South Africa, Mr McGown also said he only found out after his release that his mother had died in May this year.
He described how he learned some Arabic during his time in captivity, and his captors offered him clothing, food and medication.
Islamic extremists in northern Mali have made significant sums of money during the last decade by kidnapping foreigners and holding them to ransom.
Mr McGown said he did not know whether a ransom was paid for his release. Mediators say the extremists initially demands ten million euros per captive.