Back in verse twelve, the Day of the Lord, is now upon the high mountains and hills.
If you have ever been to a place where there are surrounding high hills, or mountains, or even standing on the top of hills or mountains such that you can view the surrounding hills or mountains, then you have no doubt been held in the awe of its beauty and presence.
And just as the cedars and oaks possess a sort of beauty and power, so too, the mountains and high hills possess a sort of beauty and power that can hold the viewer in awe.
But unlike the cedars and oaks, the mountains and hills often times hold a place of refuge in their caves or caverns, or boulders and forests that exist upon them.
It is difficult to find someone in the mountains and hills if they are hiding and do not want to be discovered.
So this verse adds to the prior verses, in that the arrogance of people can be viewed as lofty and fortified, but when the Day of the Lord arrives then these seemingly powerful and safe places, hold no such security.
They will tumble just as a house of cards would tumble with but a slight bump.
Recall our study in Revelation, when at the end of the Tribulation, the mountains and hills throughout the entire world, on this entire planet, will crumble to the level of the plains, as the continents will undergo a massive reconfiguration, making only Jerusalem the highest elevation on the planet.
The mountains and hills hold no power, no security, nothing that will contribute to the safety and wellbeing of the individual. Arrogance and indifference toward truth hold no such power.
One cannot prove themselves. One cannot lift themselves above the sins of humanity. One cannot correct or repair the fundamental flaws of humanity. We have already seen in the Psalms, the total depravity of man, and that this furthers that thought. That just as man cannot originate good, so too man cannot protect himself through arrogance.
All indifference or rejection of Gods declared mandates, and attempts to replace them with mans conveniently invented and self-serving righteousness, will fail horribly and miserably.