Warning: This article contains spoilers for Wheel of Time season 1, episode 4.
What happened with Mat Cauthon (Barney Harris) at the end of Wheel of Time season 1, episode 4 can be explained by the ruby-hilted dagger. Mat has alarmed both Rand (Josha Stradowski) and Thom (Alexandre Willaume) with his recent behavior. The way he’s been acting has played into Moiraine’s theory about one of the Two Rivers villagers being the Dragon Reborn.
Four episodes in, Amazon’s Wheel of Time show has already pointed the finger at two different characters in regards to the Dragon Reborn mystery. Episode 4 strongly hinted at Nynaeve (Zoé Robbins) being the one Moraine (Rosamund Pike) and Lan (Daniel Henney) have been looking for, but she’s not the only one that’s fallen under suspicion as of late. There’s also Mat Cauthon, who Thom has identified as a person who may be able to channel the One Power. If he’s right, that would likely mean to Rand that Mat is the Dragon Reborn and the real subject of Moiraine’s mission.
The scene in Wheel of Time episode 4 where Rand and Thom found the dead family in the house was clearly meant to imply that Mat had succumbed to the madness Thom warned Rand about. However, Mat wasn’t the murderer, nor is he suffering from anything related to the One Power. The real reason behind what’s happening with his character is the ruby-hilted dagger, the weapon he used to point out the Fade (or Eyeless) hiding in the room with them. It stands to reason that the Fade – and not Mat – was the real killer in episode 4. This means that Mat didn’t actually do anything evil, but he still could if the dagger remains in his possession. In Robert Jordan’s Wheel of Time books, the ruby-hilted dagger left a dark taint on Mat’s soul.
The dagger he found in Wheel of Time episode 2 was also recovered by the book version of the character, who experienced some harrowing ordeals just from carrying it. Cursed with the same evil power that destroyed Shadar Logoth, the dagger warped Mat’s personality. It’s obviously having the same effect on Mat in the TV adaptation, as evidenced by his delusions and paranoia. As things stand, Rand has yet to discover the hold the dagger has on him, and is more concerned about the possibility of him being a One Power channeler. For this reason, Rand’s current objective may be to avoid Moiraine and the Aes Sedai at all costs.
While Thom seemingly has Mat’s bests interests at heart, his advice to Rand in Wheel of Time episode 4 could hurt rather than help Mat in the long run. Thinking that the Aes Sedai will gentle him just like they did to Thom’s nephew, Rand may end up keeping Mat from the people who could very well have the knowledge and the resources needed for him to overcome the evil taint of the ruby-hilted dagger. Mat’s condition is sure to worsen until the characters find a way to cleanse Mat’s soul of the dagger’s influence.