The sons of Joel - The line of succession here given must be broken by one great gap or several smaller ones, since nine generations before Tiglath-pileser would carry us back no further than the reign of Rehoboam.
SDA Bible Commentary (limited)
Volume 1-7
4. Sons of Joel. The line of Joel is traced in vs.4-6 to the time of Tiglath-pileser (745-727 b.c.). Since only eight generations are given, there must be large gaps in this genealogical line.