A great starting point, of having an opinion in situations (only, if it is asked), is to look, whether there is a fact or not, and especially having some self-knowledge! This is not the same, as being self-righteous. Although, there can be truth and everyone deserves a good defence! What is the difference, between being righteous and being self-righteous?
Baptized or not;
Faith or self-importance;
Lawful or godless;
Kind or selfish;
Moral or immoral;
True or dishonest.
People can believe, but that doesn't mean, that their actions are always righteous. Someone can be righteous and have actions, that defends that righteousness (of Him, by the Spirit); enjoy, not envy, a righteous Summer!