Genesis 11

5 But when the Lord came down to look at the city and the tower, 6 he said:

These people are working together because they all speak the same language. This is just the beginning. Soon they will be able to do anything they want. 7 Let’s go down and confuse them! We’ll make them speak different languages, and they won’t be able to understand each other.

8,9 So the people had to stop building the city, because the Lord confused their language and scattered them all over the earth. That’s how the city of Babel*11.8,9 Babel: In Hebrew "Babel" sounds like "confused." got its name.