Though by the end of Final Fantasy X some people had begun to question them, nevertheless the teachings of Yevon were millennium-old and heavily influential. The Yevonite clergy taught that Sin was a divine punishment set upon the people for their pride in the use of machines. As a result, the temples forbade the use of modern technology, and promoted a culture of atonement for past sins in the hopes of appeasing Sin. While the Yevon church forbids most machina including weapons, their capital Bevelle retains machina to ensure its dominance. The Al Bhed are seen as dangerous to the Yevon clergy because they use machina and pose a threat to the church's uncontested control of Spira. The church retains its power by role in using the Final Summoning which results in the sacrifice of the summoner and her guardian to prevent its secrets from being divulged. Though Yevon set up Operation Mi'ihen to instill further loyalty to the teachings by making the Crusaders use machina that would never win against Sin.