The demons and atheists are always prepared to give trouble to the devotees. Sometimes the demons like Kamsa are prepared to kill God even. During Lord Caitanya's time Thakura Haridasa was also persecuted and put into jail. Not only that, he was whipped in twenty-two market places, but still the demons could not come out successful in the snubbing down of the Hare Krsna Movement. So do not be worried about this. Go on about your business. Krsna will give you all help, rest assured. Simply stick to you work seriously and sincerely.
Letter to Upendra, 15 July, 1970