17 Jesus said to his disciples: “Things that cause people to stumble are bound to come, but woe to anyone through whom they come. 2 It would be better for them to be thrown into the sea with a millstone tied around their neck than to cause one of these little ones to stumble. 3 So watch yourselves.
“If your brother or sister[a] sins against you, rebuke them; and if they repent, forgive them. 4 Even if they sin against you seven times in a day and seven times come back to you saying ‘I repent,’ you must forgive them.”
The only thing necessary for the triumph of evil is for good men to do nothing.