"yei kṛṣṇa-tattva-vettā sei guru haya"

One who knows Krsna, he is guru.  (Shri Caitanya Mahaprabhu)

It does not matter whether one is a brāhmaṇa, śūdra, gṛhastha or sannyāsī

If one knows Kṛṣṇa, he is a guru.  (CC Madhya 8.128)

Go Beyond the Body. Deeper Into Service.