26 Heb “the ancient path.” This has already been referred to in Jer 6:16. There is another “old way” but it is the path trod by the wicked (cf. Job 22:15).
27 Heb “ways that are not built up.” This refers to the built-up highways. See Isa 40:4 for the figure. The terms “way,” “by-paths,” “roads” are, of course, being used here in the sense of moral behavior or action.

In other versions

ESVEnglish Standard Version

But my people have forgotten me;

they make offerings to false gods;

they made them stumble in their ways,

in the ancient roads,

and to walk into side roads,

not the highway,

NIVNew International Version (2011)

Yet my people have forgotten me;

they burn incense to worthless idols,

which made them stumble in their ways,

in the ancient paths.

They made them walk in byways,

on roads not built up.

CSBChristian Standard Bible

Yet my people have forgotten me.

They burn incense to worthless idols

that make them stumble in their ways

on the ancient roads,

and make them walk on new paths, not the highway.

NLTNew Living Translation

But my people are not so reliable, for they have deserted me;

they burn incense to worthless idols.

They have stumbled off the ancient highways

and walk in muddy paths.

LEBThe Lexham English Bible

But my people have forgotten me.

They make smoke offerings to the idols,

and they caused them to stumble in their ways, the ancient ways,

to go into bypaths, not one that is built up.

KJV 1900King James Version

Because my people hath forgotten me, they have burned incense to vanity, and they have caused them to stumble in their ways from the ancient paths, to walk in paths, in a way not cast up;

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