Apostles
Later in the Gospel narratives the twelve apostles are described as having been commissioned to preach the Gospel to "all the nations", regardless of whether Jew or Gentile. Paul emphasized the important role of the apostles in the church of God when he said that the household of God is "built upon the foundation of apostles and prophets, Christ Jesus himself being the cornerstone".
Although not one of the apostles commissioned during the life of Jesus, Paul, a Jew named Saul of Tarsus, claimed a special commission from the risen Jesus and is considered "the apostle of the Gentiles", for his missions to spread the gospel message after his conversion. In his writings, the epistles to Christian churches throughout the Levant, Paul did not restrict the term "apostle" to the Twelve, and often refers to his mentor Barnabas as an apostle. The restricted usage appears in the Revelation to John.
Judas Iscariot
Ehrman argues that Judas's betrayal "is about as historically certain as anything else in the tradition", pointing out that the betrayal is independently attested in the Gospel of Mark, in the Gospel of John, and in the Book of Acts. Ehrman also contends that it is highly unlikely that early Christians would have made the story of Judas's betrayal up, since it reflects poorly on Jesus's judgement in choosing him as an apostle. Nonetheless, Ehrman argues that what Judas actually told the authorities was not Jesus's location, but rather Jesus's secret teaching that he was the Messiah. This, he holds, explains why the authorities did not try to arrest Jesus prior to Judas's betrayal. John P. Meier sums up the historical consensus, stating, "We only know two basic facts about [Judas]: (1) Jesus chose him as one of the Twelve, and (2) he handed over Jesus to the Jerusalem authorities, thus precipitating Jesus' execution."