Hebrews 10:27

Instead, [there will be] a fearful expectation of [coming] judgment and of [God's] raging fire which will consume His enemies.

Hebrews 10:31

It is a terrifying thing to fall into the hands of the living God.

Revelation 6:15-17

And the kings of the earth, the princes, the military commanders, the rich people, the influential people and every slave and free man hid themselves in the caves and among mountain ledges.

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
Instead, [there will be] a fearful expectation of [coming] judgment and of [God's] raging fire which will consume His enemies.
Revelation 6:15
And the kings of the earth, the princes, the military commanders, the rich people, the influential people and every slave and free man hid themselves in the caves and among mountain ledges.