One of the earliest known references-if not the earliest-to the Mending was contained in the Stone Book of Fay. Fay's words were in reference to her husband Flint's Stone Sword, noting that "When the Mending [came], it [would] be unmendable." This prophecy was later recounted after the Stone Sword was recovered--whole and unbroken--following the betrayal of Desolation.
Among the signs of rabbitkind's continued belief in the Mending was the use of the code phrase "a friend of the Mending" as a means of entering Harbone Citadel. This code had fallen out of usage by the time of Helmer and Picket's arrival their on their way to First Warren.
The Mending is mentioned several times, as the rabbits of Natalia prepare for and fight the Siege of First Warren, with the generally-held belief that the outcome of the Siege would either be The Mending or their utter defeat at the hands of Morbin Blackhawk.
Subsequent to Smalden Joveson's slaying of Morbin Blackhawk (which resulted in the breaking of the Stone Sword of Flint in fulfillment of Fay's prophecy), The Mending becomes a reality, as every foe that ever stood against rabbitkind had been brought to an end. The rediscovery of Firstflower perpetuates every life and heals every wound, so that The Mending would last forever.