When is counsel to be given publicly?

The advice is to call for righteousness and forbid corruption, and it should be in secret, not openly; because showing it openly is a rebuke and a taunt. The difference between rebuke and advice lies in secrecy and openness. The believer conceals and advises, while the wicked exposes and taunts. The Salaf [pious predecessors] disliked enjoining good and forbidding evil openly, preferring secrecy, because the advisor does not intend to spread faults but to remove corruption.