Runes (Symbol)
In this novel rune is not just a tattoo, which is drawing on the skin of shadowhunters, neither are they some pictures in the book. It is a part of each shadowhunter and one cannot stop being shadowhunters like to change a blood group. Runes can give power, an excellent eyesight, and invisibility. It also can trace a location of the person and gives an opportunity to see in the darkness. The rune is a symbol of the shadowhunter’s helper, not just a part of him, but the essence which presumes who he is.
Mortal Sword (Symbol)
The Mortal Sword is the second and very important symbol of this novel. It is stored in the City of Bones in the Silence Brothers. This Sword is also used like a lie-detector to test liars. Brothers often pierce Nephilims, who are suspected of lie, and check the veracity of the words. The Inquisitor also tries to check Jace, but the sword is stolen by Valentine. This Mortal Sword is a symbol of the truthfulness and justice, which can stop dishonesty and lie in the world.
Another world, evil, shadowhunters (Motif)
These three motifs discover the major theme of this interesting and exiting novel. Another world exists. It is just enough to look closely, to make some steps, which can choose you to be elected for the meeting with something supernatural and extraordinary. But this world is not good, because there are many magical creatures and demons, which are fighting for the supremacy. The blood flows like water and the struggle between evil and good is endless there. Everybody struggles for the sake of one’s life. Shadowhunters protect the humanity from cruel demons, who want to get unlimited power over the Earth. And the soul of the humanity is dependent on shadowhunters, who can change this dangerous world and make it better.