But when Escriva started teaching this, some Jesuits in the 1940s did not understand him. They said his beliefs were against the Catholic faith, because at that time Catholics thought that only priests and nuns could become holy. Some Jesuit leaders started saying that Opus Dei had secrets which it did not want the world to know, and that Opus Dei was dangerous. In fact, they said, Opus Dei just wanted to become very powerful and to control the world.