One verse

Srimad Bhagavatam 4.23.9

4.23.9

सनत्कुमारो भगवान् यदाहाध्यात्मिकं परम् । योगं तेनैव पुरुषमभजत्पुरुषर्षभ: ॥ ९ ॥

sanat-kumaro bhagavan yad ahadhyatmikam param yogam tenaiva purusam abhajat purusarsabhah

sanat-kumarah
Sanat-kumara
bhagavan
most powerful
yat
that which
aha
said
adhyatmikam
spiritual advancement of life
param
ultimate
yogam
mysticism
tena
by that
eva
certainly
purusam
the Supreme Person
abhajat
worshiped
purusa-rsabhah
the best of human beings.

Thus the best amongst human beings, Maharaja Prthu, followed that path of spiritual advancement which was advised by Sanat-kumara. That is to say, he worshiped the Supreme Personality of Godhead, Krsna.