What's the difference between the ancient poem "Joining the Army" and the first three sentences? What are the benefits?

Seven Poems of Wang Changling Joining the Army (Ⅱ)

The new sound of pipa dance is always the old love. I can't listen to endless worries, and the high autumn moon shines on the Great Wall. The first three sentences are lyrical, and the last one is scenery. Take the scene as the knot, and contain feelings in the scene; Create artistic conception, implicit and infinite. The first three sentences of the poem are all lyrical, and the word "endless" is used when it comes to "border sorrow", so how to finish the sentence in a limited number of seven words is the most obvious skill. The poet made a gentle gesture here in order to have sex with the scenery. It seems that after the scene of buying wine and drinking music in the army, a vast and desolate scene of the Great Wall reflecting the moon suddenly appeared: the ancient and majestic Great Wall was undulating, the autumn moon was shining high, and the scene was magnificent and sad. How do you feel about this? Is it infinite homesickness? Is it an ambition to make meritorious deeds or a sorrow for reality? Perhaps, you should also add a deep love for the mountains and rivers of the motherland, and so on. Therefore, the greatest advantage of writing in this way is that it is "intended outside the poem" and sublimates poetry. It makes people feel such rich and profound thoughts and feelings, and shows the inner world of the guardian incisively and vividly. Every time I read Wang Changling's poems, I have a feeling that I am the king of the four wonders.