CC Ādi 7.11
āpanā āsvādite kṛṣṇa kare bhakta-bhāva
Although Kṛṣṇa is the reservoir of all pleasure, He has a special intention to taste Himself by accepting the form of a devotee. It is to be concluded that although Lord Caitanya is present in the form of a devotee, He is Kṛṣṇa Himself. Therefore Vaiṣṇavas sing, śrī-kṛṣṇa-caitanya rādhā-kṛṣṇa nahe anya: “Rādhā and Kṛṣṇa combined together are Śrī Kṛṣṇa Caitanya Mahāprabhu.” And as Śrī Svarūpa Dāmodara Gosvāmī has said, caitanyākhyaṁ prakaṭam adhunā tad-dvayaṁ caikyam āptam: Rādhā and Kṛṣṇa assumed oneness in the form of Śrī Caitanya Mahāprabhu.