In LDS teaching there is often a minor mistake often made in explaining the Light of Christ, but this mistake can have dramatic consequences in the minds of LDS children.
The light of Christ often defined by LDS Missionaries as the conscience, enabling people to judge good from evil. But according to doctrine, the conscience is only a manifestation of the Light of Christ. But if you judge by the Book of Mormon, the Light of Christ must also be the thing that allows you to see salvation from the conscience. A critical doctrine in the LDS Faith is that Adam and Eve were sent from the garden with a specific sort of enlightenment: (1) the knowledge of good and evil, and (2) a knowledge of their inevitable salvation from good and evil. The Books of Abraham and Moses establish that Adam and Eve knew about Christ from the time they left the Garden. Symbolically, the temple ceremony must mean that (1) all humans have a conscience, and (2) they have the capacity to understand their ultimate salvation, even before Jesus taught about it. This understanding is assumed, before any priesthood, and any of the covenants. This must be the Light of Christ.
The temple ceremony also must mean that parents have the responsibility, before anything else, to teach their children to distinguish good from evil and to choose the right, and the inevitable salvation from their wrong choices in Christ. Children must be taught that their salvation is inevitable in Christ, just as it is inevitable that they will fail to do good in nearly every choice they make. To not teach the full light of Christ, is to fail to teach the first principle of the Gospel. Without being enlightened in the mind somehow by the light of Christ it is not possible to have faith in Jesus Christ.
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