Was Jesus an Historical Figure?

I forgot to add this, then remembered again - reponse

Not one of your three references amounts "evidence". They are opinions.
Evidence, for example:
Question:
Did Julius Caeser exist?
Answers:
1. An unflattering portrait of Caesar found near Tusculum, carved during Caesar's own lifetime. Later portraits invariably showed Caesar wearing a laurel crown – to hide his receding hairline.
2. There are coins surviving from the relevant period with Julius Caeser's name and portrait.
3. Contemporary Witnesses to Caesar
i. Cicero - Orations and Letters provide eyewitness evidence of Caesar
Marcus Tullius Cicero (106-43 BC) was almost an exact contemporary of Julius Caesar. In Caesar's struggle with Pompey, Cicero, governor of Cilicia, sided with Pompey but was subsequently pardoned by Caesar.
In March of 44 BC Cicero was a witness to Caesar's murder, though he was not a part of the conspiracy.
Following the assassination, Cicero made a series of speeches known as the "Philippics" which called on the Senate to support Octavian against Mark Antony. Cicero's "Second Phillipics" was an eulogy of Caesar's conquest of Gaul.
Unfortunately for Cicero Octavian reached a temporary rapprochement with Antony, who then ordered Cicero's murder.
Among some 900 preserved letters to and from Cicero are correspondence both about and with Caesar.
"... if Caesar does lose his head all the same, Pompey feels only the deepest contempt for him, trusting in his own and the state's troops..."
Cicero to Atticus, 7.8, 50BC.
ii. Sallust - Caius Sallust (86-34 BC) tribune, provincial governor and supporter of Caesar. His testimony is in a history "Bellum Catalinae".
iii. Nepos - Cornelius Nepos (c100-24): "Life of Atticus".
iv. Catullus - Gaius Valerius Catullus (c84-54 BC): "Carmina".
v. Asinius Pollio - Gaius Asinius Pollio (76 BC-4 AD) was an ally of Caesar and founder of the first public library in Rome. He was a source used by Plutarch.
vi. Virgil - Virgil (70BC-17AD): "Aeneid".
vii. Ovid - Ovidius Naso (43BC-17AD): Metamorphoses".

Near Contemporary Witnesses

i. Velleius Paterculus (c19 BC-32 AD): "Historiae Romanae".
ii. Lucan (Marcus Annaeus Lucanus, 39-65 AD) followed the example of his grandfather, Seneca the Elder – a young contemporary of Caesar – who in later life wrote a history of Rome. Lucan wrote his own Pharsalia approximately a century after the civil war it chronicles, using Seneca's work as an eye-witness source.
iii. Plutarch of Chaeronea (45-120 AD) was a Greek moralist, historian and biographer (and priest of Delphi). He wrote his Parallel Lives (matching Greek with Roman lives) during the reigns of Trajan and Hadrian. He describes in detail the life and assassination of Julius Caesar (as well as Marcus Brutus and Mark Antony).
iv. Appian of Alexandria (c.95-165 AD): Civil Wars.
v. The most famous biographer of Caesar, Tranquillus Suetonius, wrote his Lives of the Twelve Caesars during the reign of emperor Hadrian (117-138). Suetonius was in charge of the imperial archives and in this capacity, had access to some of the best possible information.

When you can find "evidence" of that caliber then you have proof. But "Jesus: A New Vision" by Marcus Borg was published in 1991, and not 2,000 years ago. It is not evidence. Likewise, "The World's Religions" by Huston Smith; 1991 (if I have the correct version). I cannot verify your lecturer.

There is no evidence for the existence of anyon called Jesus Christ who did all those things we read about in the Bible. It is a myth. And one based upon many previous versions of the same myth. Tell me, do you think that all those previous telling so this myth were the work of your Devil?