
Though its purpose used to not be common knowledge and a well-kept secret, known only by a select number of individuals, including or exclusively the Iron Sisters, it became known by other Shadowhunters after Isabelle and Clary asked the Sisters, and the news spread among the Downworld after Maia Roberts overheard the conversation about it at Magnus's apartment. The Silent Brothers protected the sword with their life, especially Brother Jeremiah, who held onto and refused to let go of the sword until his death. Later that evening, the Sword was stolen by Valentine Morgenstern, who intended to activate it to decimate the Downworlders.

Some weeks after, the Sword was used to question Jace, this time overseen by the Clave representative Victor Aldertree.
#SWORDS AND SOULS MISSING CHILDREN TRIAL#
The Sword was later used for the trial of Isabelle Lightwood at the New York Institute, overseen by Inquisitor Herondale and Brother Jeremiah. It worked to an extent, but most of her taken memories remained lost.

In 2016, Clary went to the City of Bones to let the Brothers use the Sword to access her blocked memories. According to Sister Cleophas, it would be impossible to turn off once activated. When wielded by someone with angel blood and struck with a bolt of lightning, the sword would release heavenly light that would destroy all demon-blooded creatures, namely demons and Downworlders, in its path. By design, the sword's secondary purpose can be activated with angelic energy-by the touch of someone with pure angel blood, like an angel, or someone like Clary Fairchild. The mural of the Sword at the Citadel, depicting its destructive property. This process can kill a person not strong enough to withstand its power. The Soul-Sword is held, dangling, above the person's head and the truth is "carved" from his/her mind. It has its limits, as it would be unable to retrieve memories taken from the individual. The Soul-Sword can also be used to allow a Shadowhunter to recover his/her own memories, especially blocked ones. It can also be safely used on Downworlders. Every time it is used, a Silent Brother is present to handle the sword. The Sword is also present during Nephilim trials, during which people involved or set to give statements are asked to hold the sword and swear to tell the truth.

Its truth-drawing powers can be painful, particularly when the person being interrogated with the sword struggles or hesitates to give an answer and will continue to hurt until the person gives an answer as if the sword pulls and forces the truth out from them. The sword's primary purpose is to compel the truth out of a person. The Soul-Sword is kept by the Silent Brothers in the City of Bones. The Soul-Sword, also known as the Mortal Sword, is the one of the three Mortal Instruments given by Angel Raziel to the first Shadowhunter. – Brother Jeremiah, The Descent Into Hell Isn't Easy
