LDS Church leaders teach that certain doubts can be resolved by "instruction, study, and prayer, which result in increased testimony, which drives out further doubts." However, disbelief in certain core doctrines (e.g.: the role of Jesus Christ as Savior and Redeemer; sustaining the leaders of the church as fulfilling their roles as prophets, seers, and revelators; etc.) can prevent a Mormon from participating in certain activities, such as priesthood ordinances and temple worship. Some Mormons keep certain doubts secret in order to participate in such activities, or to avoid conflict with family and friends.