A/N: I think "the river shall end at the source" was a great and wasted opportunity for the Show to explore. So, I explored it.
The river shall end at the source…
Sam had that phrase engraved into the pad of paper in front of himself. He had it typed on his computer screen. He had it playing on an endless loop in his tired brain. If he was going to save Dean - and he was going to save Dean - he had to figure out what that meant.
The river shall end at the source…
"Hey," Dean said as he came into the library carrying two mugs. He set one in front of Sam and took a seat across the table.
Great, coffee. Sam needed it. "Thanks."
"Yeah."
Dean didn't ask 'find anything?' anymore and Sam didn't offer 'not yet,' to reiterate that he wasn't giving up. He wasn't giving up, but talking about it wasn't helping either of them, so they didn't talk about it.
But he kept working on it.
He took a sip out of his mug and was surprised to taste hot chocolate instead of coffee. "This is good," he said. Dean shrugged as he got to work on his own computer.
The river shall end at the source…
River of what? Sam thought for the millionth time. River of death? River of blood? River of rage and desperation? If that was the river, then the source was Cain. But he was dead and the river hadn't stopped.
The source. Was Cain the source? Cain and the Blade together were the source, weren't they? The source of death and despair and rage and blood -
The river ~ of blood ~ shall end at the source…
And the source of the blood was -
"Hey, Dean?"
"Yeah?"
"Blood. The river shall end at the source. It's a river of blood."
"Okay…" Dean drew the word out like he knew Sam thought he should understand immediately, only he didn't.
"So, it ends at the source of the blood."
"Which was Cain."
"No. The blood came from Abel. I mean Cain's the reason it started to flow, but the blood came from Abel."
"Okay," Dean said again. "So that means what?"
"If the river ends at the source then - the river of blood ends at Abel?" Sam said, switching his brain over to puzzling that conundrum.
"Even if we knew what that meant, do we even know where Abel is?"
"Heaven? Cas must know. Or be able to find out."
"And what are we supposed to do with him if we find him?"
"I don't know," Sam admitted. He took another healthy swallow of hot chocolate.
"Even if he can do something, Cain is dead, so -" Dean said but he didn't finish his thought. He looked down at his arm like he was considering something.
"What?"
"It's not Cain," Dean said. "It didn't start with Cain. It started with the Mark of Cain. If it's a river of blood, it started when Cain accepted the Mark and killed Abel. Killed his brother. Now I've got the Mark and -" He pressed his hand against the Mark. "It's not Abel," Dean said. "It's you."
"Me? Why me?"
"Cain said the Mark was leading me along his path, but backwards. He started by killing Abel."
"And what? You've got to kill me?"
"Apparently that's what the Mark thinks. What the Mark wants. Cain said - he said I'd kill Crowley, then Cas, then I'd kill you."
"And will that remove the Mark?"
"Are you kidding?" Dean asked. "No. No. Are you seriously considering me killing you?"
"No," Sam answered. "Obviously not." Or not that obviously. "It's just - Cas could bring me back."
Dean huffed and rolled his eyes and dropped his chair down on all four legs. "Not happening." He shoved his cup aside and pulled his computer closer and stared hard at the screen. Sam went back to his computer, his paper, and his thoughts.
After a while, Dean looked up from his computer. "It's not blood," he said. "The source isn't the blood or Cain or Abel or the Mark. It's what drove Cain to agree to the Mark in the first place. That's the source."
"And he agreed to the Mark because - ?"
"To save his brother from hell."
"You already saved me from hell. A few times. And I'm not currently in danger of going back there."
"Maybe it's not literal hell."
"Then what? Metaphorical hell? Because you've saved me from that a few times, more than a few times, too."
"From – Cain's hell?" Dean said. "Maybe – I mean, yeah, sure, he wanted to save Abel from hell, but maybe Cain wanted to save himself from the hell of his brother going to hell."
"Okay, but still – I'm in no danger of going back."
"Yeah. So - it started with Cain not trusting his brother to make the right decision."
"So, river of mistrust?" Sam asked. "And it ends with you trusting me to make a right decision? Wow. I guess the Mark is permanent."
Dean tossed Sam his own version of bitchface. "Shut up. Let's think about this. It started with Cain believing what Luci said. He said he was going to make Abel is his pet. He didn't say Abel agreed to it or wanted it. He only said he was going to do it."
"He's an angel, he can't lie."
"That's not a lie. Not technically," Dean said. "He said what he wanted to do, not what Abel wanted. And we only have Cain's word for what really went down. Abel might not have had any idea what was going on." He looked down at the Mark again. "The river ends at the source..."
"A river of lies?" Sam asked. "Or obfuscations if not outright lies. Tricks, maybe? Getting Cain to take the Mark in the first place sounds like a trick. Like Crowley getting you to take it was a trick."
Dean shrugged in agreement. "Maybe what Metatron said is a trick, then, too. Or he's lying by telling the truth. I mean, think about it, the snake told Adam and Eve that if they ate the apple, they wouldn't die. And they didn't, not right then. They thought he meant ever, but he didn't specify. So, what is it we think Metatron means and what might he mean instead?"
"For that, all we have to do it figure out what the words 'river', 'shall', 'end', 'at', 'the', and 'source' mean," Sam said and added with sarcastic cheerfulness, "No problem."
"Not a problem for you," Dean said. "Not the actual meanings. What's a river? What's the source of a river? What – or how or where – is the end of a river?"
Sam inhaled a yawn and had another swallow of hot chocolate. It wasn't coffee but it would have to do to keep him awake.
"Okay, well, at its most basic level a river is a large quantity of a flowing substance. So, what's flowing with the Mark? Anger, rage, the need to kill anything and everything? What's the source of that?"
Dean shook his head. "No, we're not there yet. Just the basics. What's the source of a river. Any river?"
"Headwaters," Sam said. "That's what the source is called, whether it's rain or melting snow down a mountainside or out of a lake or, less frequently, from underground."
"So, the source of a river, the source of all that water is...water," Dean said. "Great. And what's the end of a river?"
"That's called the mouth of the river. All rivers end by flowing into another body of water, a lake or ocean. Some end by going underground. But it's still water flowing into water."
Dean rubbed his forehead. "This is giving me a headache. Water that comes from water and goes to water. Around and around in circles." He sighed and drank his hot chocolate. "Maybe that's the point. Maybe Metatron just wants us to go in circles trying to figure this out."
"Faking us out, like with the snake tricking Adam and Eve by telling only part of the truth," Sam said. "He says the river ends at the source, so we think he's talking a circle, but maybe – like you said – it's the same thing as water starting and ending with water. The river of – whatever, anger, rage, the need to kill – maybe it started with that, even before the Mark, and it ends by flowing into more of the same."
"So, by 'end' he could means 'empties out into', not 'ceases to exist entirely'," Dean said.
"Yeah."
"So, maybe all he was saying is what we already know, that to get the Mark off of me, someone else has to take it. It doesn't cease to exist, it just -" Dean gestured over the Mark. "Flows out of me into someone else. Which leaves us only slightly better off."
"Or he said whatever just to say something and get away from us," Sam offered.
"To get away from me," Dean said, but Sam didn't answer him. "So, really, we have no way of knowing what he meant."
"Yeah. I'm not sure even Occam's Razor could help us with this."
"Occam's Razor?" Dean asked. "Can I cut Metatron's throat with that?"
Sam huffed but it ended on a chuckle. "Occam's Razor basically says the simplest explanation is usually the correct one."
"The simplest answer is that Metatron is jerking us around."
"Yeah," Sam agreed. "Can we risk going with that?"
"Can we risk spinning our wheels and wasting time looking for an answer that doesn't exist?"
Sam shook his head. " I think there is an answer and Metatron knows what it is."
"Yeah, but he's kind of out of range."
"Maybe Cas can get him out, give me the chance to ask him what he means."
Dean gave Sam a hard look, a 'no, I don't like that' look that Sam pretended to not see. "Well," Dean said after a moment. "That's not happening tonight, so you might as well get some sleep."
"I'm not done."
"You're done for tonight. It's past midnight and you need rest. Why do you think I gave you hot chocolate instead of coffee? Less caffeine to keep you awake."
"Dean -"
"Sam," Dean said in his 'I'm serious' voice. "I know you're not done, all right? I know you're not going to give up. I know that. I know –" He stumbled on whatever he was going to say and moved on. "All I'm saying is you're exhausted and you need sleep. That's all. We'll get started again in the morning."
"I know. It's just –" Sam looked at his books and notes and computer, the continual thought or feeling that he could be this close to figuring out how to save Dean pressing on him to stay awake, to stay on the hunt for the answer. "I need to get this done. I need to save you."
"To save people from me," Dean supplied.
Sam shook his head. "To save you," he said again and Dean gave him another silent stare for a several moments. An unspoken disagreement.
"Okay," Dean finally said. "But that river of knowledge in your brain shall end if the source dries up from lack of sleep. And you know it. So – let's go."
Sam closed his eyes a moment, trying to summon the strength, physical and otherwise, to argue his point with Dean. But closing his eyes felt so good and the thought of even a few hours of sleep tugged too insistently.
"All right. All right, yeah, you're right," he said. "A few hours and I can get started again."
Dean huffed and glared, silently arguing with Sam's 'few hours' comment, but he didn't push it. They stood up and Dean took the cups and they both headed for the bedroom hallway.
"You don't have to follow me, you know," Sam said.
Dean gestured with the dirty cups. "Taking these to the sink."
"Going the long way."
After a brief hesitation that was proof he knew he'd been busted, Dean testily nodded Sam toward his room. "Just go to bed, Sam. All right? Bed."
Sam smiled, he thought maybe the first he'd smiled in days. The river of bossiness and care that was his life had its source in Dean, and that was never going to end. "Yeah. I'll see you in the morning."
"Yeah, the morning," Dean answered with mock gruffness. But he reached out as Sam turned away and put a hand around the back of Sam's neck. "Night," he said, before going to the kitchen.
Sam watched him go, already making plans to contact Cas and get Metatron to spill his guts, literally if necessary. "Night," he called, then added to himself. "I will save you."
The End.