What thoughts and feelings are expressed by the couplet on the neck of Jitiansheren?

The neck couplet of "Jitiansheren" expresses the author's joy for the arrival of spring.

Jitiansheren should be Jietiansheren, a five-character poem written by Wei Yingwu, a poet in the Tang Dynasty. The neck couplet is "The mountain is bright, the night is raining, the wind is warm, and the flowers are blooming", which means: the mountains are bright, the rain at night has stopped, the weather is getting warmer, and all kinds of flowers are blooming.

This sentence depicts the scene of a hundred flowers blooming after the rain, and expresses the author's joy for the arrival of spring. At the same time, Su Yuji also hinted at the author's thoughts and blessings for his friend, hoping that he could usher in a bright future after difficulties like spring.