Who is Jeconiah? We find him in the first chapter of Matthew:

And Josiah the father of Jeconiah and his brothers at the time of the exile to Babylon.

After the exile to Babylon: Jeconiah was the father of Shealtiel, — Matthew 1:11-12 BSB

So he’s in Jesus’ genealogy, but so are a lot of other people known only by being in genealogical lists. Let’s look further.

“As surely as I live,” declares the Lord, “even if you, Coniah  son of Jehoiakim king of Judah, were a signet ring on My right hand, I would pull you off. In fact, I will hand you over to those you dread, who want to take your life—to Nebuchadnezzar king of Babylon and to the Chaldeans.