sarvathaiva duruho 'yam
sarvatha—in all respects; eva—certainly; duruhah—difficult to be understood; ayam—this; abhaktaih—by nondevotees; bhagavat-rasah—the transcendental mellow exchanged with the Supreme Personality of Godhead; tat—that; pada-ambuja-sarvasvaih—whose all in all is the lotus feet; bhaktaih—by devotees; eva—certainly; anurasyate—are relished.
" 'Nondevotees cannot understand the transcendental mellows experienced between the devotee and the Lord. In all respects, this is very difficult, but one who has dedicated everything to the lotus feet of Krsna can taste the transcendental mellows.'
Link to this page: https://prabhupadabooks.com/cc/madhya/23/100