ChristianAnswers.Net WebBible Encyclopedia
See: Matthew 1:11-12
“It was Jechoniah whose sins caused God to cut his seed off from ever sitting on David's throne (Jeremiah 22:24-30). …Jechoniah's royal line of descendants is listed here [in the genealogy of Matthew 1] to show the legal right of Joseph, the foster father of Jesus, to David's throne (Matthew 1:16). Neither Joseph nor any others of Jechoniah's seed could ever have the spiritual right to the throne. That right must be carried through Mary's ancestry” (Dr. Henry M. Morris, The Defender's Study Bible, note for Matt. 1:11.).
“Coniah is an abbreviation of Jeconiah (1 Chronicles 3:16), which is another form of the name Jehoiachin (2 Kings 24:6). Coniah was the last king of Judah in the direct line from King David. When he was deported to Babylon by Nebuchadnezzar (2 Chronicles 36:10), Coniah's uncle Zedekiah was assigned to rule Judah for a brief reign, but he also was put down, and no later king was ever able to regain the throne” (Dr. Henry M. Morris, The Defender's Study Bible, note for Jeremiah 22:24.).
For more information about this man, see Jehoiachin.