His testimony began on Monday morning, the Olympian telling the court he is plagued by nightmares and wakes to the smell of Reeva Steenkamp’s blood.

Fighting back tears, he told of one night he woke up in such a state of terror he "climbed into the cupboard" of his bedroom and, when he could not calm himself down, despite knowing a security guard was outside his door, he called his sister Aimee who came and sat by him.

The court adjourned 20 minutes early on Monday, after hearing the Olympic and Paralympic track star was exhausted and had not slept at all the previous night. Judge Thokozile Masipa agreed Mr Pistorius looked and sounded tired, so agreed to his barrister Barry Roux’s suggestion that they adjourn before he moved on to a new topic in his evidence.

That topic is likely to be the events of February 13 and 14, 2013, in which Pistorius will be asked to detail exactly what happened up to and including the moments he shot and killed the model and law graduate.

He is then expected to face a formidable opponent in chief prosecutor Gerrie Nel, a man renowned for his cross-examination.

In carefully orchestrated testimony on Monday, Pistorius told the court about his double-amputation shortly after birth, his close-knit family, his late mother who encouraged him to see his disability was no disadvantage, his charity work, and his firm religious faith.

It was a markedly different side of the athlete, who the state painted as a gun-loving, trigger-happy, arrogant and reckless young man.

Mr Pistorius’ legal team wants the judge to believe Pistorius was a man so fearful of violent attacks that he was indeed capable of shooting an intruder through the toilet door of his home, as he maintains.

In that vein, Mr Pistorius described being aware of crime as far back as his childhood.

“Everyone in South Africa has been exposed to crime at some point,” he said. “My mother, she had a pistol. She often would get scared at night and she would phone the police ... She kept her firearm in a padded bag under her pillow.”

While the court has previously heard from police that Mr Pistorius has never reported to them being a victim of crime, he nonetheless detailed several incidents in which he claims to have been shot at, followed home and burgled, among other things.

The defence is also trying to establish that he felt defenceless without his prosthetic legs, which he  did not have on the night he shot and killed Ms Steenkamp. The double-amputee told the court he had limited mobility and balance without them, adding that his dog could knock him over if he wasn’t wearing his false limbs.

Mr Roux told the court on Monday he would call between 14 and 17 witnesses in the defence case.

Earlier, Mr Pistorius once again appeared to heave and retch in the dock as his legal team’s first witness, pathologist Professor Jan Botha, described Ms Steenkamp’s injuries as part of his testimony – and her bloodied skull was again flashed up on the screens in court.

Mr Pistorius denies intentionally killing Ms Steenkamp, saying he shot her believing she was an intruder.

The athlete told the court he has not picked up a gun since the incident, and never wanted to again.

The case, and Mr Pistorius' evidence, continues on Tuesday morning.