The Gospel is supported by at least 4 written testimonies: Matthew, Mark, Luke and John as well as oral witnesses of many disciples of Jesus which forms the foundation of Christianity. There would not have been around 2 billion Christians today if the early disciples did not spread this Gospel.

1. If the disciples preached the Gospel for popularity or gain, they would not have included incidents which makes them look bad, for example:
   • Jesus correcting the mistakes of Peter (Mark 8:31-33), Thomas (John 14:5-7), James and John (Mark 10:35-45), the mother of James and John (Matthew 20:20-28)
   • Arguments among all the disciples (Luke 22:24-27)
   • All the disciples' lack of faith (Matthew 14:22-33)
   • Some disciples' failure to heal a demon-possessed boy (Mark 9:14-29)
   • All the disciples abandoning Jesus in a crisis (Mark 14:50-52; Matthew 26:56)
   • Peter's denial (Luke 22:54-62)
2. The very same disciples who wrote these books, initially fled and denied Jesus in the face of persecution (Matthew 26:56; Mark 14:50-52; Luke 22:54-62; John 18:15-18). From this we know that they are human and that they were not masochist. However, for the sake of the Gospel, to proof that it is true, it was important enough to them to go through with the persecution, for example:
   • Matthew was possibly stabbed to death according to the apocryphal text, "Martyrdom of Matthew".
   • Mark was burned to death after being dragged by horses through the streets of Alexandria, according to the apocryphal text, "Martyrdom of Mark".
   • Luke was hanged on an olive tree according to the apocryphal text, "Acts of Peter"
   • John was boiled alive in oil, but miraculously survived according to the apocryphal text, "Acts of John"
3. Jesus prophecies came true:
   • Jesus predicted his betrayal, suffering, and death at the hands of the authorities (Matthew 26:24)
   • Jesus foretold his resurrection after three days (Matthew 16:21)
   • Jesus prophesied the destruction of the Jerusalem temple by the Roman army (Matthew 24:1-2; Mark 13:1-2); Some scholars belief Matthew and Mark were written around 50 AD and the event only took place 70 AD
   • Jesus prophesied that his Gospel will be preached throughout the world (Matthew 24:14)
4. Early Christian writings support the Gospel like:
   • The letters of Paul
   • Hebrews
   • James
   • Peter
   • John
   • Jude
   • The Revelation from John of Patmos
5. Roman historians support the events of the Gospel:
   • Tacitus: In his "Annals", he mentions the execution of Jesus by Pontius Pilate and the existence of early Christians in Rome.
   • Suetonius: In his "Lives of the Twelve Caesars," he briefly mentions Christus, likely referring to Jesus, and the persecution of his followers under Claudius.
6. Jewish historian support the events of the Gospel:
   • Josephus: In his "Antiquities of the Jews," he mentions James, the brother of Jesus, and his execution by the Jewish high priest Ananus. While not directly referencing Jesus, this account confirms the existence of Jesus' brother and the potential for conflict between early Christians and Jewish authorities, as alluded to in the Gospels.
7. Archaeological evidence:
   • Discoveries in Judea and Galilee, including the Pool of Bethesda, the ruins of Capernaum, and the Second Temple in Jerusalem, offer archaeological context for the locations and settings mentioned in the Gospels. These findings, while not directly proving the Gospels' narratives, demonstrate the historical reality of the places and contexts described.
8. People that gets converted by the Gospel, is supposed to change (Romans 6:4; 2 Corinthians 5:17) so that they
   • live according to a new lifestyle (Galatians 5:19-24) led by God's Spirit;
   • live in peace with God (Matthew 3:15; 1 Peter 3:21)
9. Believers in the Gospel of Jesus the Christ, have access to God's power...

And these signs will accompany those who believe:

• in my [Jesus] name [authority] they will cast out demons;
• they will speak in new tongues;
• they will pick up serpents with their hands; and
• if they drink any deadly poison, it will not hurt them;
• they will lay their hands fon the sick, and they will recover.”

-- Mark 16:17-18

Questionable texts

Luke 16:19-31

Luke wrote:

Inasmuch as many have undertaken to compile a narrative of the things that have been accomplished among us, just as those who from the beginning were eyewitnesses and ministers of the word have delivered them to us, it seemed good to me also, having followed all things closely for some time past, to write an orderly account for you, most excellent Theophilus, that you may have certainty concerning the things you have been taught. -- Luke 1:1-4 (ESV)

Therefore, it would be a terrible "eyewitness" or "account" if Luke recorded that Jesus was telling fables or promoting Greek mythology instead teaching the Word of God. This would not bring any certainty, but rather confusion, yet according to Luke 16:19-31, it seems like Jesus did exactly that. If Jesus words are taken literally it means:

• God hates rich people, because no other reason was stated why the rich man was sent to Hades (Luke 16:19-21). This creates the impression that God expects His children to be poor and uncomfortable (Luke 16:25).
• Abraham is God the Father (Luke 16:22,24).
• Hades, the realm of death in Greek mythology is real (Luke 16:23).
• People like Lazarus which are on Abraham/God's side would forever have to face how the wicked get tormented (Luke 16:23).
• Abraham/God have no mercy and would watch people getting tormented for eternity (Luke 16:24).
• People are immortal and not truly dead (Greek mythology), because they can communicate with each other. (Luke 16:24-31)
• The great chasm of Greek mythology is real (Luke 16:26).
• It is possible for the dead to communicate with the living (Luke 16:27-28).
• Abraham was not concerned that it was illegal for the living to communicate with the dead. Instead, he was concerned that they will not be convinced by the dead. (Luke 16:29-31)
• Jesus reasoning is flawed, because Jesus quoted Abraham/God saying "they will not be convinced if someone should rise from the dead" (Luke 16:31), yet in John 20:26-29 it did happen that Thomas repented when he saw that Jesus had risen from the dead.

Some argue that this is a "parable", in the light that Jesus was reasoning with the Pharisees. Apparently the Pharisees believed in Greek mythology and Jesus was speaking their language to convince them not to be greedy. As with all other parables, the focus should be on the message which is about greed and not on the technical details of Hades (often translated as "hell"). Most parables makes no sense when interpreted literally or analyzed scientifically.

However, most parables are clearly indicated by the authors to avoid confusion, for example Matthew 13:18,24,31,33,36; 15:15; 21:33; Mark 4:13,30; 7:17; 12:12; Luke 5:36; 6:39; 8:4; 12:16; 13:6; 14:7; 15:3; 18:1,9; 19:11; 20:9; 21:29. In this case Luke omit to specifically indicate that these words were intended to be understood as a parable. Also in other parables, the characters do not have names as these are not important for the purpose of the parables. Yet Jesus specifically names "Lazarus" which ironically means "God has helped", although we see that Lazarus received no help at all.

In the previous parable Jesus already addressed the issue of greed or the attempt to serve both God and money (Luke 16:1-13). Then Jesus moved on and addressed pride (Luke 16:15), the changing of laws (Luke 16:16-17) and then address the issue of divorce (Luke 16:18).

I find it strange that Jesus would jump back to the previous issue of money again in Luke 16:19 when it was already addressed. Unlike the previous parables, there are also no conclusion, explanation nor are any reaction from the audience. Could it be that this text was an uninspired addition by the church to scare the Greek to pay their pardons to the priests in fear of eternal tormenting?

John 21

Some people reason that John 21 is an addition which was not originally written by John, because:

• Some believe the language and style differs.
• John 20 concludes the witness of Jesus, but John 21 jumps back to another resurrection occurrence which breaks the text's chronological flow.
• John 21 refers to John in the third person.

Although some manuscripts lack John 21, some of the most early manuscripts did include John 21.

A possible explanation is that someone else wrote the Gospel on behalf of John because he was an illiterate fisherman and that this author possibly added his own commentary at the end which some copiers might have removed or included depending on their view.