A verse in praise says:
An iron awl without a hole
Was hurled right in his face.
Neither the message nor the letter was delivered;
Mount Kun Lun toppled over.
On Mount Chin, the locust tree was concealed by clouds;
Rain fell on Bear Ear's peak.
The rock path was slippery;
Hence thistles were sown.
An iron awl without a hole. An iron awl without a hole cannot be called an iron awl. It can only be called an iron bullet. But it cannot be a bomb or an atomic bomb. I would modify its name from "iron awls without holes" to iron bullets, because iron bullets don't have holes. Wouldn't it be more logical if we called it a pair of iron bullets?
Was hurled right in his face. It was tossed right in his face, just like a hand grenade.
Neither the message nor the letter were delivered. Communication was cut off, and so letters did not reach their destination. All contact was cut off, and no information could pass through.
Mount Kun Lun toppled over. Mount Kun Lun was turned upside-down. This is known as "moving the mountains and turning over the seas." This does not mean the mountains are transformed into seas.
On Mount Chin, the locust tree was concealed by clouds. This locust tree is probably on the Chin Mountain Range. On the Chin highland, this tree is covered by clouds.
Rain fell on Bear Ear's peak. It rains on the summit of Bear's Ear Mountain. The Dharma rain sustains the living beings on this great earth.
The rock path was slippery. The Rock ("Shr Tou") refers to the person who delivered the letter. He was most skillful and cunning. That is one way to interpret it. It could also be explained that a street paved with stones is not easy to tread upon. It is very slippery. You should be cautious and mindful—don't fall.
Hence thistles were sown. Because it is too smooth, thistles have been planted so that it won't be so slippery. These are all analogies and riddles, known as the "Ch'an banter" of the Dhyana School. You should view from the opposite angle. Don't interpret it superficially for that would be "falling into the pit" and being ensnared in the trap.