SB 5.14.5
tatra gato damsa-masaka-samapasadair manujaih salabha-sakunta-taskara-musakadibhir uparudhyamana-bahih-pranah kvacit parivartamano ’sminn adhvany avidya-kama-karmabhir uparakta-manasanupapannartham nara-lokam gandharva-nagaram upapannam iti mithya-drstir anupasyati.
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
Sometimes the conditioned soul in household life, being attached to material wealth and possessions, is disturbed by gadflies and mosquitoes, and sometimes locusts, birds of prey and rats give him trouble. Nonetheless, he still wanders down the path of material existence. Due to ignorance he becomes lusty and engages in fruitive activity. Because his mind is absorbed in these activities, he sees the material world as permanent, although it is temporary like a phantasmagoria, a house in the sky.
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
The following song is sung by Narottama dasa Thakura:
ahankare matta haña, nitai-pada pasariya,
asatyere satya kari mani
Due to forgetting the lotus feet of Lord Nityananda and being puffed up by material possessions, wealth and opulence, one thinks the false, temporary material world to be an actual fact. This is the material disease. The living entity is eternal and blissful, but despite miserable material conditions, he thinks the material world to be real and factual due to his ignorance.