Hebrews 10:27

but only the dreadful prospect of judgment and that blazing indignation which is to devour God's enemies.

Hebrews 10:31

It is a fearful thing to fall into the hands of the living God!

Revelation 6:15-17

The kings of the earth, the nobles, the officers, the rich, the strong??verybody, slave and free??id themselves in the caves and among the rocks of the mountains.

Treasury of Scripture Knowledge

Summary

That they feared greatly, because Gibeon was a great city, as one of the royal cities, and because it was greater than Ai, and all the men thereof were mighty.

Bible References

They feared

Hebrews 10:27
but only the dreadful prospect of judgment and that blazing indignation which is to devour God's enemies.
Revelation 6:15
The kings of the earth, the nobles, the officers, the rich, the strong??verybody, slave and free??id themselves in the caves and among the rocks of the mountains.