CC Ādi 6.111

avatāra-gaṇera bhakta-bhāve adhikāra
bhakta-bhāva haite adhika sukha nāhi āra
Word for word: 
avatāra-gaṇera — of all the incarnations; bhakta-bhāve — in the emotion of a devotee; adhikāra — there is the right; bhakta-bhāva — the emotion of being a devotee; haite — than; adhika — greater; sukha — happiness; nāhi — not; āra — any other.
Translation: 
All the incarnations are entitled to the emotions of devotees. There is no higher bliss than this.
Purport: 

All the different incarnations of Lord Viṣṇu have the right to play the roles of servitors of Lord Kṛṣṇa by descending as devotees. When an incarnation gives up the understanding of His Godhood and plays the part of a servitor, He enjoys a greater taste of transcendental mellows than when He plays the part of the Supreme Personality of Godhead.