SB-3.9.10 purport — To understand what is actually religion is very difficult even if one is situated in the principles of morality and nonviolence. It is very confidential because as soon as one is conversant with the real principles of religion, he is at once liberated to the eternal life of bliss and knowledge. Therefore, one who is not situated in the principles of devotional service to the Lord should not pose himself as a religious leader of the innocent public. The Isopanishad emphatically forbids this nonsense in the following mantra:

andham tamah pravishanti ye sambhutim upasate tato bhuya iva te tamo ya u sambhutyam ratah

(Isopanishad 12) A person in ignorance of the principles of religion who therefore does nothing in the matter of religion is far better than a person who misguides others in the name of religion without reference to the factual religious principles of devotional service. Such so-called leaders of religion are sure to be condemned by Brahma and other great authorities.

March 15 1974 Vrindavana

Prabhupada: So, that is natural. If you give good instruction to a rascal, he'll be angry. Murkhayopadesho hi prakopayati na shamayati. Murkha, a rascal, if you give him good instruction…  He's a rascal. He'll be angry.. Murkhayopadesho hi prakopayati na shamayati. Just like a snake. You feed the snake with milk. It will increase the poison. That's all. Practically attract. That is the Hare Krishna movement will practically attract the people. ..So we have to educate people gradually. And by our example, living example, we'll have to attract. 

Madhya 1.218 purport

The word upeksha means neglect. One should neglect an envious person. A preacher's duty is to love the Supreme Personality of Godhead, make friendships with Vaishnavas, show mercy to the innocent and reject or neglect those who are envious or jealous. There are many jealous people in the dress of Vaishnavas in this Krishna consciousness movement, and they should be completely neglected. There is no need to serve a jealous person who is in the dress of a Vaishnava