Joshua 24:2

And Joshua said to all the people, “This is what the Lord, the God of Israel, says: ‘Long ago your fathers, including Terah the father of Abraham and Nahor, lived beyond the Euphrates and worshiped other gods.

Note Hebrew the River; also in verses 3, 14, and 15

BSB · Berean Standard Bible
And Joshua said unto all the people, Thus saith the Lord God of Israel, Your fathers dwelt on the other side of the flood in old time, even Terah, the father of Abraham, and the father of Nachor: and they served other gods.
KJV · King James Version
Joshua said to all the people, “The Lord, the God of Israel, says, ‘Your fathers lived of old time beyond the River, even Terah, the father of Abraham, and the father of Nahor. They served other gods.
WEB · World English Bible
And Joshua said unto all the people, Thus saith Jehovah, the God of Israel, Your fathers dwelt of old time beyond the River, even Terah, the father of Abraham, and the father of Nahor: and they served other gods.
ASV · American Standard Version

Related passages

From the Treasury of Scripture Knowledge, grouped by the word they explain.

Your fathers
Genesis 11:26, 31; Genesis 12:1; Genesis 31:53; Deuteronomy 26:5; Isaiah 51:2; Ezekiel 16:3
served other gods
In the case of Abraham this was probably the case, till he was called to the knowledge of God, when above 70 years old.
Joshua 24:15; Genesis 31:19, 30, 32, 53; Genesis 35:4