St. Augustine
"Not to oppose error is to approve it;
and not to defend truth is to suppress it;
and indeed to neglect to confound evil men, when we can do it, is no less a sin than to encourage them."
Pope St. Felix III
"The greatest obstacle in the apostolate of the Church is the timidity or rather the cowardice of the faithful."
Pope St. Pius X
"When lies have been accepted for some time, the truth always astounds with an air of novelty."