'Ancestor's' in the Bible

"Therefore, the LORD God of Israel has declared, "I did, in fact, say that your family and your ancestor's family would walk before me forever,' but now the LORD declares, "Far be it from me! The one who honors me I'll honor, and the one who despises me is to be treated with contempt.

The time is coming when I'll cut away at your family and your ancestor's family until there are no old men left in your family.