Archbishop Emeritus Desmond Tutu and his wife Nomalizo Leah have renewed their wedding vows as they celebrated 60 years of marriage in South Africa last week.

A ceremony was held at St George's Cathedral, Cape Town, marking their actual wedding anniversary on July 2. Another service was held on Saturday at Holy Cross Anglican Church in Soweto, Johannesberg, which was attended by former South African President Thabo Mbeki and Nelson Mandela's widow, Graca Machel.

The couple met at college and now have four children and seven grandchildren. They said at the cathedral service on Thursday that their ability to laugh at and with each other at kept their marriage strong, EWN reports. They kept giggling throughout the service, struggling to keep a straight face as they renewed their commitment to each other.

Desmond Tutu became a prominent anti-apartheid campaigner and voice for peace in the 1970s and was awarded the Nobel Peace Prize in 1984.

He has often honoured his wife for the support she has given him. During the service he said to Leah: "I owe all that I am to you, and God was very good to give you to me – even if you do put up placards that say 'you are entitled to your wrong opinion'."

Their youngest daughter, Rev Mpho Tutu, officiated the ceremony.

Their son, Trevor, told SABC that the secret to their marriage was "very simple" according to his mother. "It is because she has never, ever contemplated divorce. She has thought about murder a couple of times but divorce, never."