kiśora vayase - just before the beginning of His youthful life; ārambhilā - began; saṅkīrtana - the saṅkīrtana movement; rātra-dine - night and day; preme - in ecstasy; nṛtya - dancing; saṅge - along with; bhakta-gaṇa - the devotees.

Just prior to His youthful life, He began the saṅkīrtana movement. Day and night He used to dance in ecstasy with His devotees.