In the Fourth Age, it was believed that there was "balance" in Gielinor between the god of order, Saradomin, and the god of chaos, Zamorak. It was also believed that if either god were to upset this balance by attempting to attack the other, another God War would begin. If the Edicts were violated, a select group of Guthixians would re-awaken Guthix, causing him to remake the world without mercy for beast or man, destroying Gielinor as known by its modern inhabitants in the process. This was clarified in the Origin Of Gielinor and The World Wakes, as the Edict of Guthix was made to ban all higher tier gods from the world to avoid them from causing any more destruction to it, and it could not be broken, unless Guthix were to die.
Though Saradomin and Zamorak were the main deities battling each other by the time Guthix awoke from his slumber, the Edicts also affected Bandos, Armadyl, Marimbo, V, Tumeken and Elidinis, though the rest of the Menaphite Pantheon and the other minor deities were allowed to remain because of their lesser powers and influence. Seren never left, but instead turned herself to crystal and shattered, which left her pieces across the forest. It was long thought that Zaros was not bound by the Edicts but as stated, it was proven that even he was bound.
Darkness of Hallowvale
During Darkness of Hallowvale, werewolves from the vampyre kingdom of Morytania were able to cross the blessed River Salve into Misthalin. They were sent by the vampyre Lord Drakan to kidnap humans for blood tithes. When King Roald, king of Misthalin, wanted to start a new war with Morytania, his advisor Aeonisig Raispher reminded him that starting a war would break the Edicts of Guthix. Since then the church of Saradomin began investigating the Edicts. During the Legacy of Seergaze quest, a group of followers of both Zamorak and Saradomin, who are working together to bring down the Edicts of Guthix, are discovered.
Shadow of the Storm
When speaking to Juna the snake, there is a possibility of mentioning the Shadow of the Storm quest. After telling her about it, Juna states that Agrith-Naar found a way to get around the Edicts. It was thought that there were other ways to get around the Edicts, as is being looked into in the Myreque quest series.
The Temple at Senntisten
More recently, during the quest The Temple at Senntisten, one helps Azzanadra restore the Altar of Zaros in the Digsite Dungeon, the site of an ancient Zarosian city. Azzanadra then succeeds in contacting Zaros, who apparently inhabits a distant plane. Although Zaros does not come to Gielinor's plane at this time, some of his power is manifested on Gielinor, including damaging a statue of Zamorak at the Chaos Temple. This manifestation was theorised to have violated the Edicts of Guthix. If this was indeed a violation, it is not known whether it was intentional or not, as the Edicts were proclaimed during the God Wars, long after Zaros has disappeared from the plane of Gielinor. Speaking to Juna after having done the quest will reveal that Zaros's return would shift things towards balance as she says that Zamorak is but a pretender god. However in response to the story after telling her of The Firemaker's Curse, she says she cannot look kindly to Zaros's return. This was thought that Zaros was not bound by the Edicts in the same way that other deities were.
2009 Hallowe'en event
In the 2009 Hallowe'en event, the Spider Queen reveals that the Edicts command the Grim Reaper to have the scythe, the bones, the robes and a spooky house decorated by spiderwebs. As the Grim Reaper cleans all the spiderwebs, the Spider Queen puts a spider in his bath. He must be convinced to put all the spiderwebs back, in order to restore the Edicts. This may conclude that the Spider Queen is a Guthixian or she is afraid of violating the Edicts of Guthix.
Destruction of the Edicts
Following the events of The World Wakes, which culminate in the death of Guthix himself at the hands of the Mahjarrat Sliske, the Edicts are destroyed, bringing an end to thousands of years without interference from the gods and allowing them to once again return to Gielinor, essentially ushering in a new Age. Furthermore, it is revealed in a Behind the Scenes video that the Edicts formed an actual physical, magical wall around Gielinor. As it broke, it shattered and dissolved into purely magical energy spreading all around Gielinor. The Gods and their followers were searching to gather the energies, in hope of accessing its power in combination with the Stone of Jas.
In Hero's Welcome, Sigmund the Merchant mentions that the Edicts were not a singular event, but a series of bans as the gods were slowly expelled from Gielinor. The gods who actively fought were the first to be removed. Gods who tried to run away and hide were also dismissed. Gods who were peaceful or agreed to leave, such as V, were given a chance to say a proper goodbye to their followers.
In the quest, as V was injured and losing energy, he did theorise that Guthix may have left a "barb" such that any returning gods would be injured, but he felt that this would not have been probable as Guthix was dead and the Edicts null.
Interference of gods post-Edicts
The gods nonetheless have left imprints and echoes of their terrible power on Gielinor and its plane, such as Saradomin's power remaining strong upon Entrana and blocking even teleporters from carrying armour and weapons to his sacred island, even through intermediate realms as the Abyss. Various objects, some of which are very common and easily attainable throughout Gielinor, such as the Holy symbol of Saradomin's silver star, have been blessed by some of the gods' most pious followers with small portions of their tremendous power, aiding them when they are praying. The River Salve, along with the Salve shards that have absorbed some of the river's holy energies, has been blessed by Saradomin's power to secure the lands of his followers against the immense threat of Morytania (though this is less direct, as the quest River of Blood reveals it was blessed through blood magic by the Seven Priestly Warriors), as well as the god of order himself granting the Gaze of Saradomin to the Temple Knights (watching over them, his loyal followers), enabling them to respawn at Falador.
Additionally, gods can influence events in RuneScape through Prayer to countless followers, mainly human. Zamorak is able to frequently attack humans who attempt to steal his wine with mystical flames, considerably lowering one's stats, albeit inflicting relatively minimal damage. The mid-level spell Divine Storm can be utilised by especially skilled practitioners of Magic, and draw upon the power of the gods themselves. Even seasoned adventurers fear the wrath of the gods, as they dare not use anything on their altars. Seren is still able to power elven magic through items such as the crystal bow, the crystal ward and the crystal chime, as well as communicate with her followers through the Tower of Voices, and all but one of her nine mystic seals upon the Grand Library are still intact. Bandos can imbue certain objects with his power, which can allow him to influence the minds of whomever bears his items and to allow him to bring his avatar into Gielinor.
Any human bearing items dedicated to a different god than the god they are in the waiting room for is automatically forced to assume another shape temporarily, apparently due to the power of the Gielinor deities. According to the Mage of Zamorak, "the magic we have had to use to retain a portal to the abyss open and effective is derived from Lord Zamorak himself. Well, he has his occasional quirks. In this case it means that when you enter this dimension you will be 'skulled' and your prayer will be drained. That makes it somewhat more dangerous than other places you may be used to."
This is confirmed in the first RuneScape novel, Betrayal at Falador. It is mentioned in the novel that when the blood of an innocent person is spilled on a holy barrier (such as the River Salve, the Monastery of Saradomin, and Falador Castle), then the holy barrier is, in most cases, temporarily void. This is limited in its application, however, as more powerful barriers can only be bypassed by one individual for a matter of minutes or seconds, and often this process is unpredictable in its repercussions. This was used by Lord Drakan during what would come to be known as the War of 164, although the violation was not significant enough to invoke the Edicts.