You aren't showing empathy, you claimed the parents were "brick walls" with "warped perceptions" who were harming their own children, and that you specifically

You aren't showing empathy, you claimed the parents were "brick walls" with "warped perceptions" who were harming their own children, and that you specifically told them that! No wonder they got defensive. That's the opposite of trying to understand them and it's certainly not charitable to them, is it? To engage in empathy you must be able to fairly articulate their views and the reasoning they use to arrive at them, in the same way they would or even better. In both posts you haven't done that. That's why they aren't listening to you. Your response to their views is laughable, it's to say "trust me" and then try to manipulate ("guide") their child when they aren't around, which is the opposite of being trustworthy. They trusted you to tutor their child in specific subjects and instead you betrayed that trust, then act surprised when they are "brick walls"? To convince the parents, you first need to convince them to talk to you and take you seriously. That in turn requires that you, firstly, stop bringing their child into it. Just ignore the child. The child is not being harmed, you aren't a hero who's saving them. The child's views are not your business, they are the parent's business. And secondly, that you do the legwork to fairly investigate their beliefs and the evidence they found convincing, so you can debate with them directly instead of telling them about "a place of trustworthiness" that they clearly don't believe in.