 He celebrated his first Mass two days later on 21 June 1904, the Feast of St. Aloysius Gonzaga, in the Church of Nuestra Señora de Ocotlán, near the city of Tlaxcala.Tritschler went to work at the Seminario Conciliar de Mexico, which was still under construction at the time.The architect, Manuel Gorozpe, aware of Tritschler's esteem, asked his advice of the project, and was influenced to change some of the plans of the seminary.