"Not if you're being kept in the dark, and you are!" (Cliff 4x07) -> "You lied to protect someone else, and to keep me completely in the dark." (Cliff 4x08)
Cliff is upset in 4x07 that Grayson is using Fern as a pawn, setting precedent for how he feels in 4x08 when Fern does the same to him, hiding her knowledge of and involvement in the job.
"I'll be damned if I'm gonna see you get hurt in all this." (Cliff 4x07) -> "I lied to protect you, to keep you safe!" (Cliff 4x08)
Fern insists that she's not the only villain. Cliff lied too about getting an award out of town so he'd be there to bust the bootleggers. But following how her safety was his concern in 4x07, that's why he lied in 4x08.
"You're the only light in this crooked town." (Cliff 4x07) -> "You barely know me!" (Fern 4x07) -> "You saw me the way I have always wanted to see myself." (Fern 4x08)
Cliff sees Fern as sweet, the light in a town that's all wrong. She insists he doesn't know her, but in the next episode - she acknowledges that's how she wants to see herself. But of course that's hard after all her loss, running from her past, turning to performance - an act - to hide how she really feels.
"Kissing you, the way I felt, that was real. But I can't stay knowing it wasn't real for you." (Cliff 4x08) -> "For the first time in my sad little life I am not acting, I swear!" (Fern 4x08)
First, incredible honesty on Cliff's behalf. He gets nervous and embarrased around Fern when she's outright flirting, but when it counts, he always shows up.
Then specifically for Fern to say she's not acting - it's confirmation for him that it wasn't a performance. Fitting both because she's a performer, but also for how their relationship started - all banter and wit to hide behind. But he saw through to her, and she made new memories with him - good memories in a place she was only haunted by the past. Able to reframe the bad, she could move toward healing. In the process, she fell in love with him too.