“Do it,” he said.
If they—the teachers—are teaching the right thing (but not doing it themselves), what’s that to you? That’s their problem, to which they’ll have to answer.
Jesus said, “practice and observe whatever they tell you—but not what they do” (Matthew 23:2).
In other words, if the advice is good, then don’t miss out just because they’re a hypocrite. This applies to everyone from fallen TV preachers to cheating mentors.
If you throw out the good advice just because it came with a bad messenger, then everyone loses.