This is Rick at his most exposed. It’s all he could ever give of himself to another person to pick over the deepest wound that the zombie apocalypse has inflicted on him. The third season – the conclusion of all the Shane and Lori drama, the birth of Judith, the loss of his wife – is Rick’s absolute undoing. In After, it’s played as the ultimate dig when Carl mentions Shane in the midst of his anger. For Rick himself to willingly bring the whole thing back in an effort to open himself up to Michonne is huge. It’s raw and painful and beautiful. You can tell how much it means for him to say, “Judith isn’t mine” by the way he breathes out afterwards – like it’s a breath he’s been holding in since the day she was born.
Rick’s reveal here should also be considered within a broader pattern that’s forming, too. Since these two became official, we’ve seen him much more emotionally open and direct than ever. His response to Michonne shutting down in her grief is to reach out (see also: Say Yes). And while this confession shows her the sacrifices he’s made to serve his argument, an inadvertent consequence – whether conscious or not – is that Michonne’s role as a parent becomes even more legitimized. Rick’s claiming of Judith is as legitimate or illegitimate as Michonne’s of both of their children. If Rick sees Judith as his, he sees Carl as Michonne’s.
Andy: It’s one of those watershed moments that happens between the two lovers, between Michonne and Rick, that brings them together.
Danai: It’s heartbreaking and it’s astounding and it’s painful, because on the one hand she loves him and sees more of the beauty in him, but he has been holding this inside. That he made the decision that he did is what makes him a beautiful leader. He sacrifices and he gets out of the way of his own feelings to do what’s right for others. That’s what’s beautiful about him to her. That’s why she trusts him and that’s why she’s been loyal to him, and part of why she fell in love with him. […] She would never have dreamt that he wasn’t Judith’s father from the way he treats this little girl.
“The original novel [Dumb Witness] was dedicated to her [Agatha Christie’s] own wire-haired terrier - ‘To dear Peter,’ it read, 'most faithful of friends and dearest of companions. A dog in a thousand.’ I felt exactly the same way about the terrier in our film. He captivated me from the moment I set eyes on him. The little dog, whose real name was actually Snubby, became my dear friend. [..] My now ever-expanding fan club wrote to tell me how much they enjoyed it [the episode], so they also told me, the sales of wire-haired terriers shot up exponentially after it was shown for the first time in March 1996.” - David Suchet, Poirot and Me