“The Supreme Personality of Godhead said: O Uddhava, a saintly person is merciful and never injures others. Even if others are aggressive he is tolerant and forgiving toward all living entities. His strength and meaning in life come from the truth itself, he is free from all envy and jealousy, and his mind is equal in material happiness and distress. Thus, he dedicates his time to work for the welfare of all others. His intelligence is never bewildered by material desires, and he has controlled his senses. His behavior is always pleasing, never harsh and always exemplary, and he is free from possessiveness. He never endeavors in ordinary, worldly activities, and he strictly controls his eating. He therefore always remains peaceful and steady. A saintly person is thoughtful and accepts Me as his only shelter. Such a person is very cautious in the execution of his duties and is never subject to superficial transformations, because he is steady and noble, even in a distressing situation. He has conquered over the six material qualities—namely hunger, thirst, lamentation, illusion, old age and death. He is free from all desire for prestige and offers honor to others. He is expert in reviving the Krsna consciousness of others and therefore never cheats anyone. Rather, he is a well-wishing friend to all, being most merciful. Such a saintly person must be considered the most learned of men. He perfectly understands that the ordinary religious duties prescribed by Me in various Vedic scriptures possess favorable qualities that purify the performer, and he knows that neglect of such duties constitutes a discrepancy in one’s life. Having taken complete shelter at My lotus feet, however, a saintly person ultimately renounces such ordinary religious duties and worships Me alone. He is thus considered to be the best among all living entities.” (Srimad-Bhagavatam 11.11.29-32)
“The symptoms of a sadhu are that he is tolerant, merciful and friendly to all living entities. He has no enemies, he is peaceful, he abides by the scriptures, and all his characteristics are sublime.” (Srimad-Bhagavatam 3.25)
“A sober person who can tolerate the urge to speak, the mind’s demands, the actions of anger and the urges of the tongue, belly and genitals is qualified to make disciples all over the world.” (Nectar of Instruction 1)
Thus by Vedic standards, someone who engages in any form of violence towards any living being, deception, theft, lust, or materialistic, can never be called a saintly person. Only those who possess the above saintly qualities can be accepted as a genuine Swami/Guru or Prophet of God. One should only hear and learn religious values from saintly persons.