The Basics of Judaism: Jewish Texts: The Ancient Paths:
What are the "ancient paths" mentioned in Jeremiah 6:16?
The "ancient paths" are the paths of righteousness
followed by our ancestors (commentary of RaDaK).
The Midrash amplifies this: Consider in what path
Abraham and Jacob went, and in what path Nimrod and
Esau went, and which of them was successful.
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