Cults can exist within mainstream religions. In my mind many are relatively harmless. For example, the nuns I worked for were devoted to their foundress and worked for decades towards her canonisation as a saint. Focussing on this role model had positive, not negative, effects on their work and on the way the school was run. In effect it was the cult of Mary Mackillop and many people could be considered to have joined this cult because they pray to this saint, visit her shrine and make pilgrimages to places significant to her life and history.
The ones to watch are those that are secretive and which cut members off from general society and shun family members who do not belong to the cult. Extremist views and demanding strict orthodoxy are worrying signs, as is the absolute authority of a charismatic leader.
