Obedience to lawful authority is a commandment of God. So we must take it seriously and understand that just because an authority (bishop or priest) makes errors in some areas, if he is truly an authority for us, we must consider each command and measure it against what our informed Catholic conscience tells us is true.
St. Thomas Aquinas provides the formulation for determining whether a command is lawful or not:
“Law is an ordination of reason, by the proper authority, for the common good, and promulgated.”
If the bishop or priest bases his command on incomplete facts or invalid logic, then his command is not an "ordination of reason." If the person is not actually the bishop or priest with authority over you, then his command does not need to be followed by you. If his command is for his private gain or has an evil end, then he must be ignored. If he does not tell you that he is commanding you to do what he says, then it is not required.
Being obedient to a bishop's lawful command or taking a bishop's advice are two very different things. The former is a required under the fourth commandment. The latter is a matter of prudence.