Uncle: Grieved Pistorius wasn't eating
"He only started to eat last night," he told eNews Channel Africa on Wednesday.
"Carl and Aimee [Pistorius's brother and sister] tell me they sit with him and he spends a lot of time reading, especially reading the Bible, as his mother taught him."
Pistorius has been under arrest since his girlfriend Reeva Steenkamp was shot dead in his Pretoria home in the early hours of Thursday last week. He has been charged with murder, and his bail application is underway in the Pretoria Magistrate's Court.
Arnold said this had been a tough time for the family, but they stood behind the athlete all the way.
He voiced concern over what he described as his nephew's "public trial".
"The case is [on]going and you can judge for yourself ... the truth will prevail," he said.
In the TV interview, Arnold said the Pistorius family has been in contact with the Steenkamps but respected their privacy and loss.
Asked about allegations that Pistorius had a history of violence, he described Pistorius as a "peacemaker".
Pistorius was in extreme shock and was grieving in this "emotionally tough time" said his uncle.
"The world will see a different Oscar; nobody can be the same ever again if such a tragedy comes over your life, but he will bounce back and be greater than ever."
Steenkamp was cremated at a private ceremony in Port Elizabeth on Tuesday. – Sapa