A long time ago the Ori were one society...humans on an evolutionary path to ascension...

"Great holy armies shall be gathered and trained to fight all who embrace evil. In the name of the Gods, ships shall be built to carry our warriors out amongst the stars and we will spread Origin to all the unbelievers. The power of the Ori will be felt far and wide and the wicked shall be vanquished."

"Those who stray must be guided back to the path"

"Those who reject the path to enlightenment, must be destroyed"

"Those who are prideful and refuse to bow down, shall be laid low and made unto dust"