From President Thomas S. Monson:
For Latter-day Saints, the need to rescue our brothers and sisters who have, for one reason or another, strayed from the path of Church activity is of eternal significance. Do we know of such people who once embraced the gospel? If so, what is our responsibility to rescue them?
Consider the lost among the aged, the widowed, and the sick. All too often they are found in the parched and desolate wilderness of isolation called loneliness. When youth departs, when health declines, when vigor wanes, when the light of hope flickers ever so dimly, they can be succored and sustained by the hand that helps and the heart that knows compassion.
There are, of course, others who need rescue. Some struggle with sin while others wander in fear or apathy or ignorance. For whatever reason, they have isolated themselves from activity in the Church. And they will almost certainly remain lost unless there awakens in us—the active members of the Church—a desire to rescue and to save.
Read the rest of First Presidency message for October 2013 at lds.org. And get President Monson's biography, To the Rescue, at this link.
Supplemental ideas: Watch this video on how we can rescue those around us, no matter who they are or whether or not they are familiar with the Church.