CC Ādi 4.220

sei rādhāra bhāva lañā caitanyāvatāra
yuga-dharma nāma-prema kaila paracāra
Word for word: 
sei — that; rādhāra — of Śrīmatī Rādhārāṇī; bhāva — the emotion; lañā — taking; caitanya — of Lord Caitanya; avatāra — the incarnation; yuga-dharma — the religion of the age; nāma-prema — the holy name and love of Godhead; kaila — did; paracāra — preaching.
Translation: 
Lord Caitanya appeared with the sentiment of Rādhā. He preached the dharma of this age — the chanting of the holy name and pure love of God.