“The Jews therefore marveled, saying, “How is it that this man has learning, when he has never studied?”” John 7:15
We know that there were multiples sects at the time of Jesus’ incarnate life. The Pharisees and the Sadducees were predominantly featured in the Biblical discourse.
It is clear that they had never seen Jesus attend any of their rabbinical schools otherwise they would not have marveled that he was well studied.
Jesus could read Luke 4:16, therefore he was literate and consequently educated though not necessarily by a religious rabbi.
And there were other religious schools like the Essenes. Would it be out of the question Jesus was taught by an Essene? They were renown for their love for the Scriptures.
Jesus also grew up near the city of Sepphoris. He certainly used the term hypocrite which might indicate having at least been to this city and seen its amphitheater, if not attended and spectated a theatrical performance. He might have received his education from here by a religious or non religious teacher?
In light of the fact that Jesus according to Philippians 2:7 voluntarily emptied or nullified His divine attributes whilst in a human body, meaning He had to learn (Isaiah 7:15) and could not rely on His omniscience, why were these people marveling? Surely the Pharisees were not the only ones who could teach on the Scriptures? Did they hold a monopoly on religious education?
Or was it (also) a matter of costs? Jesus didn’t look/dress like he was part of high society to have afforded an education (private) in his childhood?