They were the first chance for people to remember the man many call Madiba - his tribal name - and others know as Tata, the Xhosa word for father.
Even those who once called him their enemy mourned. The Dutch Reformed Church in East Pretoria was once known as the altar of apartheid, because the Bible teachings there sought to provide a basis for racial separation.
Pastor Niekie Lamprecht remembered the fear some felt when Mandela came to power, and said: "What helped the white people of South Africa was Mr Mandela's attitude. He said let's forgive, and he forgave. That created a space for people to feel safe and change at a time when the expectation was that there was going to be a war."
Zuma told mourners in Bryanstown Methodist Church, Johannesburg: "We should pray for us not to forget some of the values that Madiba stood for, that he fought for, that he sacrificed his life for.
"When our struggle came to an end, he preached and practised reconciliation, to make those who had been fighting forgive one another and become ... a Rainbow Nation. He believed in caring and he cared for our nation. He believed in forgiving and forgave, even those who kept him in jail for 27 years."
Like many a preacher before him, Zuma caused observers to wonder if he could live up to his own words.
In the run-up to presidential elections next year, some are asking whether Zuma is tainted by corruption, as his own party, and those of his rivals, are riven by dispute.
That is something the Mandela family know about. They fought in the courts about who should have control over his financial legacy and even his bones, while the ailing patriarch was not even dead.
Mandla, the eldest grandson, who tried to have Mandela buried in his own village, to his profit, was ostracised by the family at the time. But he sat up front yesterday as Zuma spoke, alongside Winnie Madikizela-Mandela, Mandela's former wife.
Graca Machel, his third wife, has kept her usual dignified silence.
For others yesterday, there was already a sense that mourning should give way to celebration for his long life and all they feel he achieved for them. It was fitting that this should start with prayers of thanks.
At the Nelson Mandela Centre of Memory in Johannesburg yesterday, leaders of many faiths paid tribute. The country's Chief Rabbi, Warren Goldstein, said: "He was like Joseph in the Bible: he came out of jail and became President and like Joseph, he was prepared to forgive his brothers."
In Soweto, Father Sebastian Rossaw urged the congregation to be like Mandela: "God sent us ... this man who could show us - despite what was going on at the time - that the light could still shine in the night."
