TRADITION VS SCHOLARSHIP
The answer
Matthew 1:16 calls Joseph the son of Jacob; Luke 3:23 calls him the son of Heli. After King David, the two genealogies run through largely different names down to Joseph.
Why it’s interesting
Interpreters have long proposed explanations — that Luke traces Mary's line, or that an ancient custom of levirate marriage is at work — and scholars still weigh them. The text simply gives you two family trees and lets you look.
Genuinely debated
You can know the Bible.
Not just the stories, but the history, authorship, and scholarship behind it.