Contrary to Buffy the Vampire Slayer, religion is fought against in The Cabin in the Woods. The film is devoted to critiquing religion and used religious sins to argue.
The group of friends unknowingly accept to be the sacrifices for the ritual, by allowing Dana to read the passage from the diary. In the diary, there are heavy hints that the Buckner family was very religious, possibly the reason that the family was chosen to be a choice in the list of monsters. Before resurrecting the family, Dana reads from Anna Patience’s diary: “Father was cross with me and said I lacked true faith.” Dana continues to read that “[Patience’s] good arm is hacked up and et so I hope this will be readable, that a believer will come and speak this to our spirits.” Implying that when the female zombie with one arm appears later, that it is Patience’s. Patience’s is shown to have her left arm cut off, this could mean that when she hopes that her writing is readable, it’s because she was initially left handed. Since the left hand is associated with the Devil, being left handed is a sin; tying the family to Christianity even more.
If Patience’s was associated as a sinner that wanted to prove her faith, it was important that she be the one to kill the sacrifices.
To begin the ritual, Dana and Jules are chosen as sacrifices simply because of their virginity or lack thereof. Since premarital sex is a sin, it is in the rules of the ritual that the whore will die first; meaning Jules. Dana, since she is chosen to be the virgin, is required to be the last one to die, if she dies at all. Since Marty does not die when he was supposed to, the facility goes into a panic and wants to make sure that Dana lives the longest and urges her to sacrifice her friend. Dana and Marty’s ultimate decision to let the world end so that they may live, can be seen as putting their personal interest ahead of others, which frowned upon in the Bible: “do not merely look out for your own personal interests, but also for the interests of others” (Philippians 2:3-4, NASB).
Sins in The Cabin in the Woods are more apparent than others, like adultery committed by Curt and Jules. However, society has started to shift away from viewing the world with Biblical eyes and take a more modern look. The film points out the ridiculous notion of some sins, while also supporting beliefs, to please the audience.