As a greenhouse is used for the cultivation of plants, your home is used to cultivate faith in Christ for your children. Your home should provide spiritual protection from the harsh storms of daily life.
...the goal for your home is to provide the sort of greenhouse environment that will enable your children to stand in the harsh winds of the world that hates them and their Savior. Obviously, the time comes when children transition out of the home. Just as a gardener hardens his plants gradually to avoid a sudden debilitating shock, wise parents will find ways to expose their children gradually to the outside world.
(Everyday Talk: Talking Freely and Naturally about God with Your Children, copyright ©2004, pages 90 and 96)
(Photo courtesy of AdamR at FreeDigitalPhotos.net.)