Hamer puts forward an explanation for where this redefinition came from:
In Nauvoo, Joseph concentrated all power to himself as mayor, general of the militia, head of the courts, and candidate for President of the United Sates
In his final months, Smith organized a theocratic Kingdom of God with a Council of Fifty men sworn to secrecy.
On April 11, 1844, Smith was acclaimed King of the Kingdom of God on Earth at a secret meeting of the council.
Because Joseph was surrounded by yes-men who worshiped him like a king, gave him their daughters and wives, Joseph lost any sense of boundaries. This fueled his speculation that God may once have been a man, and that he would someday be a God.
After his martyr, this deification was immortalized into the song "Praise to the Man."