Actually, Tian Peng wasn't that involved in the affair, but as fate would have it, when the Monk set off on his journey to wander the Four Seas, the first place he walked toward was the northwest.
In that frigid land of the northwest, the Monk wasn't afraid of freezing himself, but the Emperor was afraid.
The Emperor feared an accident might befall his sworn brother, who was also burdened with the Emperor's nightmares. If anything happened to him, the Emperor feared he might be plagued by nightmares for a lifetime, so he wrote a letter, requesting hospitality be shown to the Monk.
Naturally, Tian Peng had no objections, but he always felt that the dim-witted Monk mentioned in the letter seemed familiar, as if they had crossed paths on the road and held a connection by fate, resembling Tang Xuanzang, the reincarnation of Jin Chanzi.