Chapter 10
6 Thus Saul died; he and his three sons and all his house died together. [1Ch 10:6 ESV]
The whole story of Saul's death is repeated here, and seems to be much like the narrative in 1 Samuel 31. 1 Samuel does not mention "all his house".
His three sons AND all his house. Were there eight generations alive all at the same time? Hard to believe Saul lived that long. I think he was only king for 40 years. Need to come back and fill this in. No help in MSB.
No...but by the time he died, Jonathan must have had at least one son, who was not found by David in his search. That's what it says right here. Only the lineage of Jonathan is mentioned, and only one son of Jonathan is mentioned. We know that Mephibosheth also survived, and that he later participated in trying to overthrow David. But the way the Bible talks about it, it is not necessary for 8 generations to all have been alive.
Also, per the MSB note in 1Sa31, Saul actually had four sons. The survivor - who was apparently not at the battle - is later called Ishbosheth, King of Israel, whom Abner backed instead of David for a time. So why does it use the term "all his house died together"? I really can't say. Perhaps Ishbosheth lived elsewhere already because of father/son problems. Maybe Saul had even kicked him out and disowned him.
2021 - "all his house" likely means those living with Saul, his sons, his advisors, his servants, and his closest friends. Remember that in the Northern Kingdom, when there was a coup, the whole house of the former king was sometimes wiped out, and this included his closest friends/advisors/supporters. That is likely what is meant here about the house of Saul. So we don't know whatever happened to Eshbaal, but he was apparently not part of Saul's house, and none of his descendants are listed.
2021 - The key seems to be that Saul had 4 sons, not just the three who died with him in battle. There is also one named Eshbaal. Here is the verse about the ones who died:
2 And the Philistines overtook Saul and his sons, and the Philistines struck down Jonathan and Abinadab and Malchi-shua, the sons of Saul. [1Ch 10:2 ESV]. No mention of Eshbaal. Are Eshbaal and Ishbosheth the same man? I found this note here, https://www.abarim-publications.com/Meaning/Eshbaal.html:
"The name Eshbaal in the Bible"
Eshbaal is one of the sons of Saul (1 Chronicles 8:33), and probably the same as Ish-bosheth (איש־בשת), who succeeded Saul as king of Israel, but who was defeated by David two years later. Eshbaal and Ish-bosheth are never openly equated, but the two names never appear side by side (which would prove that there are two different sons of Saul). Scholars assume that the relation between the names Eshbaal and Ish-bosheth is like that between the names Merib-baal and Mephibosheth — the two names of the certainly one son of Jonathan, son of Saul — namely that the baal-part of the original name, which refers to the ungod Baal, was exchanged for the word boshet, meaning shame."
Still 2021 - In chapter 8, the descendants of Saul go through Jonathan only. There is no mention in 8 of either Eshbaal or Ishbosheth. Same in Chapter 9. Eshbaal's descendants, if he had any, are not mentioned. Only the descendants of Jonathan. David, whom God established a forever covenant with, established a forever covenant with Jonathan So this may be the reason that Jonathan's genealogy is preserved. David's promises must also be kept.
13 So Saul died for his breach of faith. He broke faith with the LORD in that he did not keep the command of the LORD, and also consulted a medium, seeking guidance. 14 He did not seek guidance from the LORD. Therefore the LORD put him to death and turned the kingdom over to David the son of Jesse. [1Ch 10:13-14 ESV]
Full explanation of the reasons for Saul's death, and for the transition of the kingly line from the tribe of Benjamin to the tribe of Judah. In Genesis 49, as Jacob blesses his sons, we find this:
10 The scepter shall not depart from Judah, nor the ruler's staff from between his feet, until tribute comes to him; and to him shall be the obedience of the peoples. [Gen 49:10 ESV]
So Saul's fall could have been predicted.
In that same chapter, we find this:
27 "Benjamin is a ravenous wolf, in the morning devouring the prey and at evening dividing the spoil." [Gen 49:27 ESV]
Benjamin was short term - just morning and evening. But Judah was long term.