He also called pastors to "ask Jesus to change his plan."
President Zuma made the comments at the South African launch of an international campaign to stop violence against women and children.
South Africa's president also urged men and boys to fight domestic violence, and encouraged victims to report abuse.
According to Eyewitness News, he said: "We don't know when Jesus is coming to fetch us."
"When he was still on earth the sinners were not as many as they are now.
"He must come again to deal with us and cleanse us.
"We can't win this war alone, to protect children, we need the support of families and parents."
Jacob Zuma has made similar comments in a previous address, in September this year:
"I know they say Jesus will return to fetch us. But I don't know how many will stay behind. Maybe the majority."
"[Jesus should come] not to fetch us, but just to cleanse us of our sins, because we have caused more damage than before.
"He must just come for a few years to help us so that we are ready for when he finally comes."