Charles Spurgeon Commentary Jeremiah 9:26

"Egypt, and Judah, and Edom, and the children of Ammon, and Moab, and all that have the corners [of their hair] cut off, that dwell in the wilderness; for all the nations are uncircumcised, and all the house of Israel are uncircumcised in heart." — Jeremiah 9:26 (ASV)

Egypt, and Judah, and Edom,

You see that Judah is sandwiched between Egypt and Edom.

Those who were the people of God are put in the same category as the accursed nation, because they had forsaken him and mingled with them.

And the children of Ammon, and Moab, and all that are in the utmost corners, that dwell in the wilderness: for all these nations are uncircumcised, and all the house of Israel are uncircumcised in the heart.

If the heart is not right with God, vain are all external rites.