Śrī Caitanya Caritamrta · Text Ādi 2.61
অবতারী নারায়ণ, কৃষ্ণ অবতার ।
তেঁহ চতুর্ভুজ, ইঁহ মনুষ্য–আকার ॥ ৬১ ॥
avatārī nārāyaṇa, kṛṣṇa avatāra
teṅha catur-bhuja, iṅha manuṣya-ākāra
Because Nārāyaṇa has four hands whereas Kṛṣṇa looks just like a man, they say that Nārāyaṇa is the original God whereas Kṛṣṇa is but an incarnation.
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