The Edicts of Guthix, most prominently alluded to in the Darkness of Hallowvale quest, are apparently a series of decrees Guthix created for the world after the last God War. At the time of this writing, there is "balance" in Gielinor between the god of order, Saradomin, and the god of chaos, Zamorak. If either god were to upset this balance by attempting to invade the other, then the other god would potentially call on reinforcements from other realms. This would escalate the crisis and lead to another devastating God War. Guthix, according to legend of his followers, would then awake and wreak justice on Gielinor, remaking the world as it has never been but destroying it in the process.
The Edicts of Guthix are being investigated by Saradomin scholars for a loophole after the revelation that werewolves had crossed the Salve and kidnapped humans for blood tithes.