beḍā-saṅkīrtana tahāṅ ārambha karilā
sāta-sampradāya tabe gāite lāgilā
beḍā-saṅkīrtana - surrounding congregational chanting; tāhāṅ - there; ārambha karilā - began; sāta-sampradāya - seven groups; tabe - thereupon; gāite lāgilā - began to chant.
For an explanation of the beḍā-saṅkīrtana, one may refer to Madhya-līlā, chapter eleven, verses 215-238.