"This is the message we have heard from him and proclaim to you, that God is light, and in him is no darkness at all. (1 John 1:5, ESV).
First implication: we cannot love the world.
Light and darkness
Light and dark have often been used metaphorically to distinguish between two diametrically opposed entities, such as good and evil. Sometimes, they are used to show a balance of two necessary things (i.e., yin and yang in Chinese philosophy). In the case of John's first letter, however, it is a dividing line that cannot be crossed. If you love God, who is light, you cannot love the world, which is in darkness.
Walking in the darkness
What comes to mind when I think of walking in the darkness is trying to navigate the toy-laden path from the bedroom to the kitchen in the middle of the night. To use the metaphor of a minefield may be extreme but it captures the dangers inherent in the trek. Children love to lay stumbling blocks in their parents’ path (sometimes, they are literally blocks–the kind with sharp corners). The obstacles are only easily avoided with the help of a light. And so it is with the stumbling blocks we face in life. The Greek word skandalon found in John 2:10 may not have an etymological connection to our modern word scandal (though I would guess it does), it does speak to the dangers of loving the world. When we pursue the things the world says are inherently desirable (i.e., money, pleasure, comfort) without reservation, we can find ourselves tripped up and in a scandal.
The importance of light
This is why it is essential to have a handy flashlight when traversing the minefields of the unlit basement floor and to live with the enlightenment of God’s spirit while wandering as sojourners in the trap-laden lands in which we live. When we live in the love of God–that is, when we're walking in the light, when we're abiding (or, remaining) in God, and when we're following the commands of His son (namely, loving one another), we can avoid the dangerous stumbling blocks that cause scandal.
-Joel Fletcher