Most of those Biblical names were converted into the Greek. In fact their Aramaic names were quite different. For example Jesus was Yeshua ben Yosef, Simon Peter was Shimon Kephas, Thomas was To'am or Taoma meaning twin. The New Testament was compiled and written in the Greek so they adapted the names into Greek and we get the later Anglicised versions.
Actually the New Testament didn't exist until the 27 parts were compiled into one book if you like by Athanasius, Bishop of Alexandria in 367 AD. Many of the pieces about Christ were left out and many can be found from the Coptic material and compiled to form what is called the Nag Hammadi (I own a copy), including material called the Gospel Of Thomas (believed to be the earliest compilation of Christ's sayings written), The Gospel of Mary Magdalen, probably put in writing in the second century AD. Not unusual. Material on Buddha was not written down for a couple of centuries after he died and the Koran is believed to have mainly been compiled by Mohamed's followers based on his revelations. Fascinating subjects concerning how religions develop.