Light is both sudden and constant

8 For once you were full of darkness, but now you have light from the Lord. So live as people of light! 9 For this light within you produces only what is good and right and true. 10 Carefully determine what pleases the Lord. 11 Take no part in the worthless deeds of evil and darkness; instead, expose them. 

(Ephesians 5:8-11 NLT)

We once were full of something other than light - darkness. Where light enters, the darkness is dispelled. The light we not possess is that which comes because the presence of Christ dwells within each of us. There is no longer room for darkness, nor is there anywhere for it to hide - eventually all that is darkness will be revealed (uncovered) by the light. We are called to live as "people of the light" - no longer tolerating darkness within. That means we allow what Christ begins within us by bringing light to do the work it does - exposing every hidden thing that needs to be fully brought into the open so it may be removed and set in order.

Christ's light within either produces what is "good", "right", or "true". 

- Good refers to that which is bountiful or fruitful. Light's first "outcome" within us is to bring us from a place of just barely existing to being filled - bountiful in every way. God's light changes what has been an infertile place for his grace to become a place of ultimate fertility - ensuring there is good ground for his grace to not only be accepted, but multiplied ten and a hundred-fold. Where God's goodness dwells, there is a beauty produced that some would say is "considerably different" than what was once produced or housed in the place where darkness used to dwell.

- Right means he brings truth into areas where we have believed and embraced anything less than full truth. Where God's light is allowed to have access, the lies we once believed about ourselves, and even those we have repeatedly told ourselves, begin to be exposed for what they are - untruth. The idea of his light bringing what is "right" into our lives is that of us no longer having to live confused about whose we are, what our value really is, or how "suitable" we have been made because of his presence within. 

- True carries the idea of bringing us to the place that we retain only what is essential to life and godliness within. We shed the "other stuff" that only clutters the space of our lives - making it more confusing than it should be, or creating a lot of chaos within our emotions or thoughts. We allow his light to reveal what should remain and what should be discarded as "worthless" or "trivial" compared to the magnitude of his grace and love that desires to dwell in that place.

When God's light enters, there is a great deal of "care" taken to ensure only the goodness of God, the righteousness he brings, and the truth he declares is allowed to remain in residence. We don't casually accept Jesus into our lives, anymore than we casually see the effect of light when we flip a switch. When the switch is placed in the "on" position in a room, the light suddenly illuminates the space into which it is brought, doesn't it? The illuminating effect of light is sudden and then it is constant. Christ's grace is both - sudden in that it brings light to these areas where light needs to come, and constant in that it remains laser focused on those areas until all is set in order there.  Just sayin!