Mormon 4:12

And there never had been so great wickedness among all the children of Lehi, nor even among all the house of Israel, according to the words of the Lord, as were among this people.

There had never been such great wickedness among all the children of Lehi. There had never been such wickedness among all the people of Israel. The Lord said this was the most wicked people ever.

There had never been such wickedness among all the descendants of Lehi, or even among all the people of Israel, as the Lord himself had said. This was the worst it had ever been.