If we go back to the earliest statement of Jesus’ resurrection, in the letters of Paul, we find something very problematic. Paul quotes a creed or piece of poetry that says:
That Christ died for our sins
in accordance with the scriptures.
and that he was buried;
That he was raised on the third day
in accordance with the scriptures,
and that he appeared to Cephas, then to the twelve.
Why is this a problem? The New Testament thinkers were in the habit of inventing material about Jesus copying Old Testament scriptures. So, for instance, Mark copies material from the story of Elijah to present John the Baptist as the new and greater Elijah. Likewise, Mathew’s story about Jesus recapitulates the story of Moses to present Jesus as the new and greater Moses. That is what the above “Corinthian Creed / poetry” that Paul is quoting seems to be doing with the Old Testament story of Jonah and the huge fish. In Matthew regarding the resurrection we read:
The Sign of Jonah
38 Then some of the scribes and Pharisees said to him, “Teacher, we wish to see a sign from you.” 39 But he answered them, “An evil and adulterous generation asks for a sign, but no sign will be given to it except the sign of the prophet Jonah. 40 For just as Jonah was three days and three nights in the belly of the sea monster, so for three days and three nights the Son of Man will be in the heart of the earth. (Matthew 12:38-40)
So, far from being historical, the Easter resurrection claims are much more likely hallucinations or lies inspired by the story of Jonah.