CC Madhya 8.134

parama īśvara kṛṣṇa — svayaṁ bhagavān
sarva-avatārī, sarva-kāraṇa-pradhāna
Word for word: 
parama — supreme; īśvara — controller; kṛṣṇa — Lord Kṛṣṇa; svayam — personally; bhagavān — the Supreme Personality of Godhead; sarva-avatārī — the source of all incarnations; sarva-kāraṇa-pradhāna — the supreme cause of all causes.
Translation: 
Rāmānanda Rāya then began to speak on kṛṣṇa-tattva. “Kṛṣṇa is the Supreme Personality of Godhead,” he said. “He is personally the original Godhead, the source of all incarnations and the cause of all causes.