The Tottenham boss shouted from the witness box at prosecutor John Black QC: "You think I put my hand on the bible and told lies? That's an insult, Mr Black, that's an insult."
Bespectacled Redknapp shook his head as Mr Black ended his cross-examination at Southwark Crown Court, in London, by saying: "I suggest you have been telling the court a pack of lies."
With a voice trembling with emotion, Redknapp replied: "Everything I have told you is the truth, the whole truth and nothing but the truth, so help me God."
Both Redknapp, 64, and co-defendant Milan Mandaric, 73, deny two counts of cheating the public revenue through "bungs" worth £189,000 in a Monaco bank account.
Redknapp said he was willing to swear again on the bible as he completed his evidence by saying: "I am not a liar."
He said: "I'm the most ungreedy person you have ever met in your whole life, ever."
Redknapp earlier admitted misleading a News of the World reporter because it was the "easy way out".
He also asked Black "are we that stupid?" after it was suggested Redknapp had "let the cat out of the bag".
"Do you think me and Mr (Milan) Mandaric are going to have completely different stories," Redknapp said. "Are we that stupid?"
Redknapp said: "Sometimes I may say the wrong words but I do not do it purposely."
He said the payments were "one million percent not my bonus" and the account "was so far from my mind it was unbelievable".
He said he did not tell his accountant about it because "I had nothing to tell him, there was nothing in it".
Redknapp said he had paid £8million in taxes "so why are we going to bother?".
"I only asked Mr Mandaric once about the account - the away win at Blackburn (in 2004)," Redknapp said.
"He said 'Disaster, Harry' - I didn't ask again."
Redknapp said the account was no secret.
"I told all the boys at Portsmouth about it, I told Quest about it, that's how secret it was.
"As far as I was concerned, it was the most unimportant thing in my life, that account."
Redknapp also told a court he "plucked the wrong figure" out of the air as he was questioned by Premier League bung investigators.
Redknapp denied prosecution claims he "desperately" tried to cover up allegations the £189,000 Monaco payments were bonuses for transfer profits.
But he said he gave sports journalist Rob Beasley the wrong information to prevent a story appearing in the Sunday tabloid as Spurs were due to take on Manchester United in the 2009 League Cup final.
Redknapp said: "I don't have to tell Mr Beasley the truth. I have to tell police the truth, not Mr Beasley, he's a News of the World reporter."
When asked why he referred to payments as bonuses he was due for the sale of Peter Crouch from Portsmouth to Aston Villa, Redknapp added: "I wanted to make the point to Mr Beasley that it was paid by my chairman."
He added: "I referred to it to him many times as my Crouch bonus" as "Crouch is an easy answer".
Redknapp added: "I just want to get Mr Beasley out the way - I just didn't want a story in the paper.... I was going to come down to breakfast and all my players were going to be looking at the back page of the News of the World. It was going to be embarrassing."
When asked again why he had offered a "false story" to Beasley, Redknapp, wearing tortoiseshell glasses and a navy blue suit, added: "I just want to get him off my back. This is the easy way out for me before a Cup Final."
The payments were linked to Crouch "in my mind", Redknapp added.
"In my mind it was always related to Crouch even though it wasn't connected.
"I felt morally I was due that money even though legally I wasn't."
Tape recordings of Redknapp talking to Mr Beasley were played in court.
Black focused on Redknapp saying "Well, what did he give it to me for then?" when Mr Beasley said Mandaric claimed the payments were an investment, not a bonus.
Black asked earlier if Redknapp was "desperately trying to hide" that it was a bonus.
Redknapp replied: "Absolutely not."
He said: "I wasn't sure what the sum was, Mr Black" when he first mentioned the account to Quest Premier League bung investigators.
When asked if he plucked a figure out of the air, Redknapp replied: "I did and I plucked the wrong figure, didn't I?"
Redknapp said that if he had not told the Quest inquiry about the Monaco account the issue would be "dead".
Other football managers did not voluntarily declare accounts, he told the jury.
"As I have said many times Mr Black, If I don't go to Quest and tell them about that account, nobody knows," Redknapp said.
The 2006 Quest investigation into English football was led by Lord Stevens, the former Metropolitan Police Commissioner.
"Half the managers didn't even tell them," Redknapp said. "If I didn't tell them it's dead."
Redknapp said earlier that neither he nor Mandaric was "silly" enough to dodge tax.
Mandaric, he said, presided over "two billion US dollars companies - we're not talking about a skint member (of the public)".
Redknapp said he raised the Monaco account once because "I didn't want to embarrass him basically that he had made a loss, a bad investment".
He added: "Once I walked out of that bank, I went to the beach. I couldn't even tell you where that bank was."
Redknapp has told the court he was focused on "marking David Beckham" as he signed off a six-figure bank transfer between Monaco and Mandaric's US account in 2003.
Black referred to a Portsmouth match against Manchester United as he told Redknapp: "You didn't mark him very well."
Redknapp replied: "It didn't work - I think he scored a hat-trick."
Redknapp said: "It wasn't a loan" but he planned to repay Mandaric the money sent to his Monaco account.
His accountant had told Redknapp "Christmas has arrived" when finding out how much was in it, jurors heard.
Redknapp said: "It will be paid back, not while this case is going on, it doesn't look right.
"I will pay Mr Mandaric back once this case has finished, that's for sure."
Mandaric was said to have told Redknapp his investments were a disaster.
Redknapp said: "If it had been my money, I might have cried but it wasn't my money".
Court documents wrongly listed that Redknapp once played for AC Milan and as Black read out his playing career, Redknapp smiled and said: "I didn't play for them."
The first charge of cheating the public revenue alleges that between April 1 2002 and November 28 2007 Mandaric paid 145,000 US dollars (£93,100) into the account.
The second charge for the same offence relates to a sum of 150,000 US dollars (£96,300) allegedly paid between May 1 2004 and November 28 2007.
Redknapp, who underwent minor heart surgery last year to unblock his arteries, is the most successful English manager in the modern game, having led Portsmouth to FA Cup success and Spurs to last season's
Champions League quarter-finals.
Mandaric is now chairman of Sheffield Wednesday, having previously worked at Leicester.
Redknapp told the court of his east London upbringing before returning to the dock.
He said "no one had it harder" as he denied Black's claim that he was offering a "twisted" account.
Former Arsenal goalkeeper and television pundit Bob Wilson was called as a character witness after Redknapp returned to his seat alongside Mandaric and said Redknapp had supported a charity set up after Wilson's daughter died in 1998.
Redknapp was "very quick to understand what we do and why we do it", Wilson said.
John Kelsey-Fry QC closed the defence case by reading out a letter sent from an undisclosed witness.
The letter detailed how Redknapp invited a wheelchair-bound former Tottenham player to come and watch a training session.
The letter said: "How considerate and kind is that? I would say it is confirmation he is a giver, not a taker."
The jury was sent home until Friday when the prosecution closing speech will take place.