Ether 8:18

And it came to pass that they formed a secret combination, even as they of old; which combination is a most abominable and wicked above all, in the sight of God:

They formed a secret group, just like the people long ago. This kind of group is the worst and most evil thing in God’s eyes.

They formed a secret conspiracy, just like the ones in ancient times. These conspiracies are the most disgusting and wicked thing in God’s sight.