Spoiler warning: Heavy spoilers for the original Mistborn trilogy, some spoilers for the later Mistborn books, and references to Elantris and some Cosmere lore.
By the end of book two of the original Mistborn trilogy, Sazed, Keeper of Terris and resident religious scholar and optimist, has been crushed by loss and the meaninglessness of life.
While an expert on many different religious faiths, Sazed does not subscribe to any of them in particular but rather to “them all.” Sazed believes in providence and is generally hopeful in a positive future for the world. He maintains an optimistic stance despite the adversity in his own life and in the life of his people. The Keepers, like Sazed, were persecuted by the Lord Ruler because of their feruchemical abilities, and Terris women were forced into breeding programs in order to maintain a lack of magical abilities in new generations of the Terris people.
Sazed is a man on the margins who has somehow kept to hope and devoted his life to fighting for what is right for his own people and all the peoples of The Final Empire.
But even as Vin and Elend are at an apparent zenith in their own journey, Sazed has been brought low by the reality of death and the tragic circumstances of life.
The trigger for his despair is the death of the woman he loves, Tindwyl. Despite the odds being against them, Sazed and Tindwyl had been reunited and were spending loving hour together researching the problems plaguing the world. Though Sazed sees himself as inadequate and unfit for Tindwyl since he is a eunuch. But Tindwyl loves Sazed, and it looks as if they could truly have a meaningful life of love together ahead of them.
After Tindwyl’s death in the defense of Luthadel, Sazed thinks:
Surely her love for him had been a miracle. Yet, whom did he thank for that blessing, and whom did he curse for stealing her away. He knew of hundreds of gods. He would hate them all, if he thought it would do any good.The Well of Ascension, 725
Having no specific devotion, Sazed has nowhere to direct his pain and frustration about what has happened. Sazed experiences a depth of pain and brokenness, and his own optimism becomes a part of the problem. The open-minded relativism that protected Sazed and allowed him to cross-boundaries in the world is now part of what is destroying him and bringing him to his absolute lowest point.
Which makes him the perfect candidate for godhood.
Sazed becomes the god Harmony at the end of The Hero of Ages as he takes up the power of Ruin and Preservation. Despite his great power though, he is not omniscient or omnipotent. He has boundaries. Sazed discovers that he is only a part of “God.” As readers of the Cosmere are still learning, “God”–Adonalsium–has been broken. Those who broke “him” are now Shards of that power. Sazed is a piece of God.
It’s is Sazed’s own brokenness and discovery of the apparent meaninglessness of life that prepares him for divinity. Sazed is also a believer in and supporter of the human. Rather than looking from the heavens down, in all religions and mythologies, Sazed sees the meta-human. The various beliefs and religions that have come about on his world emerge from the people, and that’s great. So when Sazed sees that there is
a “higher power” out there, he can come at it as a broken human. God is broken, and that’s okay.