“Srila Prabhupada is explaining who within this world is intelligent.
krsna yei bhaje sei hayata catura – One who worships Krishna, he is the most intelligent.
Caitanya Mahaprabhu also said the same thing in the Caitanya Caritamrta:
krsna je bhaje se bada catur, krsna-bhakta hena chara – A person who worships Krishna, he is the most intelligent.
A non-devotee is insignificant, and his association is undesirable. In the material world everyone has forgotten their eternal relationship with Krishna. They do not remember that Krishna is the Supreme Personality of Godhead, the source of everything.
Without knowing the supreme position of Krishna, they consider themselves important and attempt to enhance their position materially. Due to this spirit, they become bound by the laws of cause and effect.
Sometimes they may rise up to heavenly planets, or they may descend to hellish planets and suffer the results of their sinful activity.”HH Jayapataka Swami
Verse 9 Purport
From the book “Vrindavane Bhajan”