The presence of light (which is the glory of God) is another protective covering for the sons of God(let your light shine in the presence of men). It is an important layer making up the manifold grace of God..

The question of the presence of light in our temples(in us) is revealed in the study ark of the covenant. It is the product of a combustion of a sacrifice of men - the oil - to produce light before God. A sacrifice is a giving of something pure/good to God, which is received by fire - signifying the power of God.

The light then becomes the witness of God to men. It is a demonstration of God's glory.

Matthew 5:16 |
Let your light so shine before men, that they may see your good works, and glorify your Father which is in heaven.

Being a living sacrifice is also another matter of fact of a spiritual nature. It is the giving of one's self to God. The sacrifice produces light out of the burning/reception by God. It is for these reasons the spirits of men are tested by their fruits, the fruits here being the light which becomes the obvious result.

Other conditions of abiding in this protective light, because, just like the lamp, it needs to be fed, include things like obedience to God and submission to authority. Being facts that can waver, and due to the vulnerability of being Human, it is important to be conscious to remain within the protective bounds of the glory of God.

Just as one can walk out of a strong city in the physical realm, the same is true for the spiritual realm because the Spirit of God cannot not imprison one against their will. So hold on to what you have.