Back in the jungle, Charlie is STILL staring at the heroin, like, just shoot it or snort it or put it on your gums or whatever other way you have of doing it that the network is able to show already. Before he can, Locke comes stomping out of the bushes, saying he's "disappointed" in Charlie. Charlie can't believe Locke followed him. "You've got the wrong idea, man," says Charlie, and Locke points out that Charlie said he said destroyed it all, and yet here it all is, so just exactly how is Locke getting the wrong idea? Charlie says that he came out here to finish the job, and I was kind of hoping that Locke was coming out here for the same reason. So Locke starts gathering up the statues into his backpack. "There was a time when I let you choose whether or not you were going to do this to yourself. And now I'm making the choice for you," says Locke, who is certainly one to talk about lies. Charlie tries to show how over the drugs he is by ripping open the Baggies he's holding, spilling the contents on the ground. Because that worked so well when he did it for Claire.
So Charlie brings up all the talks he and Locke have had about everything happening for a reason, and the island testing them, and hey! This is Charlie's test! That's why the drugs are here! Locke has an alternative theory: that the drugs are here because Charlie put them there (he could also add that Charlie's failing any tests pretty miserably -- although in Charlie's defence, we have not seen him actually have any of the heroin).
Finally Charlie starts pleading for Locke not to tell Claire, or she'll never trust him again. Given that Charlie's not very trustworthy, I fail to see this being much of a convincing argument for Locke. And Charlie finally tries to convince Locke that Aaron's in danger. "You have to believe me," he says. "You've given up the right to be believed, Charlie," says Locke, and sanctimoniously stomps off into the jungle. Although he's not wrong, exactly.
Back on the beach, Claire, carrying Aaron, strolls up to a just-returning Locke, who -- significantly, I think -- asks how "our boy" is doing. Then Claire asks if she and Aaron would be able to stay in the bedroom in the hatch for a little while. Locke points out that the snooze-alarm-on-steroids wouldn't exactly be conducive to the baby sleeping. And even though she hasn't directly said anything, Locke knows exactly why she's asking, and so he offers to move his things down the beach next to hers for the next few nights, an offer she gratefully accepts. Then she asks him if he knows anything about baptism. "Not a whole lot. Why?" She explains that Charlie said that Aaron needed to be baptized, that he's in danger. Locke ponders this, then says, "My understanding is that baptism is about making sure that children get into heaven, should anything happen. Call it spiritual insurance." He says that Aaron isn't in any danger, that Charlie just and as he says this, he opens his backpack to put in a bottle of water, and pauses, presumably because he's looking at all the Virgin Marys in there. "Charlie just feels like he has to save the baby because he can't save himself." He slings the backpack over his shoulder, says he'll see Claire tonight.