1. Judge by action, not by promises

    “One cannot understand the value of touchstone until it turns iron into gold.” One should judge by action, not by promises. A maha-bhagavata can turn a living entity from abominable material life to the Lord's service. This is the test of a maha-bhagavata.

    From Srila Prabhupada's purport to Cc Madhya 16.74