All young men in the Church should be very eager to go on a mission, and they should also help their parents to fill missions after the families are raised. Young people should study the gospel, prepare themselves for service in the Church, and keep the commandments as diligently as it is possible to do. Young people who have planned to fill missions are more fruitful, more effective, and more successful when they serve, and more people will come into the Church and will create more enthusiasm, and there will be a chain reaction. Is there any other thing than the gospel that would have a greater chain reaction and affect more interests and people?
– Spencer W. Kimball