place (someone or something) (up) on a pedestal
To believe or behave as if someone or something is perfect, wonderful, or better than others, to the extent that one is unable to see the potential flaws or faults of that person or thing. You know how Tiffany places him up on a pedestal—it's useless trying to get her to see that he's a jerk. Stephen has been placing classic literature on a pedestal ever since college, so he gets really judgmental of other genres he deems to be inferior.