1 Samuel 4

"When he mentioned the ark of God, Eli fell backward off his chair by the side of the gate. His neck was broken and he died, for he was an old man, and he was heavy. He had led Israel forty years." v.18

Read chapter 4

Why do you think it mention Eli was fat?  We may know why this detail is in here from the previous chapters more than just to describe what his physical condition was.  In chapter two we learned the wickedness of Eli's sons as priests stealing the sacrifices offered by the people for themselves to eat the fat and parts that were to be to the Lord.  We then read in 2:29, "Why do you scorn my sacrifice and offering that I prescribed for my dwelling? Why do you honor your sons more than me by fattening yourselves on the choice parts of every offering made by my people Israel?"  So we see Eli being called out for partaking in his sons wickedness and eating the robbed sacrifices too.  Because they ate all this extra food as gluttons they became fat.   So Eli falling backwards on his chair here in chapter 4 and dying isn't something that normally happens when someone falls off a chair but breaking his neck was because he was so fat as he fell over and his fat consumed him.  How have you seen wickedness of ones sons or daughters in-turn cause the parent to sin as well?