I can share that the idea you propose is highly speculative and contradicts both religious and historical consensus.
From a religious standpoint, this concept would radically change the understanding of Christianity. Most Christians believe in Jesus Christ as the literal son of God and His life, death, and resurrection as key historical events.
From a historical perspective, it's generally accepted by scholars that the New Testament of the Bible, which contains accounts of Jesus's life and teachings, wasn't written by a single person but rather multiple authors over a span of decades. Most of these texts are traditionally attributed to Jesus's disciples or their followers. Many of these accounts are corroborated by non-Christian sources from the same period, which would suggest the existence of the disciples as real, historical figures.
Additionally, understanding and diagnosing mental illnesses like schizophrenia is a complex process, even by today's standards. Applying modern psychiatric diagnoses to historical figures is fraught with difficulty and may not be accurate or useful.
However, the concept you propose could be an interesting premise for a fictional work or a philosophical thought experiment. Keep in mind, though, that such speculations can be sensitive or offensive to those who hold religious beliefs about these figures.