Alexander III participated in the reform of religious traditions and presided over the Lateran Council Aimed to further eliminate the hostile forces supported by the emperor, and called for the mobilization of the official and growing heretical movement of all Western European churches. He announced the excommunication of Albi and its followers and sympathizers. The Pope also organized a crusade in 1181 to prepare for the crusade, but it was unsuccessful. In 1179, the conference formulated the New Papal Election Law, which stipulated that only the cardinals could be eligible to be elected as popes. Those who obtained a two-thirds majority of the bishops' group were popes, and those who were elected as popes did not need to be approved by the emperor. This principle is still in use today. The meeting also stipulated that the bishop must be a non illegitimate Christian who is over 30 years old.
The Lateran meeting was attended by Waldo of Lyon, who made a poor vow under the auspices of Pope Alexander III. Later, the Waldorian sect was condemned by the Bishop of Lyon and became the next Pope Lucius III They also advocated that they should be excommunicated. This force later developed into the heresy of Waldo.
