The earliest written account of the Resurrection comes from Saint Paul.
Resurrection is a heavy word.
It is not a synonym for either resuscitation or immortality. During his early ministry, Jesus brought back to life several persons who had died, including a grown man and a young girl. The same thing happened in the Old Testament. On one occasion a Jewish soldier who had fallen in battle was buried in the tomb of the prophet Elisha. All of these people were brought back to life, to earthly existence in this world for a while.