God’s purpose in creating the universe was to end up with a heaven populated by angels - people - from the human race. All His laws, which collectively may be called the Divine Providence, are dedicated to that end. One of those laws is that people must be in freedom to choose to follow those laws or not, because only those things chosen in freedom from a love for them is lasting. This means that people may choose to do evil without obvious, external restraint from the Lord. No hand will come down out of the sky, and no terrible voice will call, “stop!”. The Lord can only work internally in each person using what the person has in his or her understanding or conscience. His overarching law that requires human freedom prevents anything else.

The evils that occur in such circumstances are called permissions. They can serve a purpose. In someone who has a conscience, and wants to do what is right, the doing of some evil or even the thought of doing some evil will bring to the person's attention that a love for that evil exists in them, and a resistance to both the thought and deed must be developed so that shunning the evil can become less difficult. When a person who doesn’t have a conscience does evil, and that evil breaks out into external acts, then others can see that open evil. If dismayed by it, they can see that they should avoid it, or if they see an incipient love for it in themselves, they can work to shun any thought of dwelling on it in their imagination, or, worse, doing it themselves. In this way the Lord can make use of evils that arise in hell. In the work entitled "Divine Providence" we are taught that the Lord never allows evils that cannot serve a useful warning purpose that may lead toward salvation.

(References: Apocalypse Revealed 686; Arcana Coelestia 1299, 2447 [2], 6489, 6574 [2-3], 8227 [2]; Divine Providence 16, 234, 251 [1-2])

16. 7. The Lord does not let anything remain divided. This means that things must be focused either on what is both good and true or on what is both evil and false. The first of the goals toward which the Lord's divine providence works is that we should be engaged in what is good and what is true together. That is our "good" and our love and that is our truth and our wisdom, because that is what makes us human and images of the Lord. However, since while we are living in this world we can be engaged simultaneously in what is good and what is false, or in what is evil and what is true--even in what is at once evil and good, and therefore double--and since this division destroys that image and therefore our very humanity, the Lord's divine providence is trying to get rid of this division in everything it does.

Further, since it is better for us to be engaged in something evil and something false than in something good and something evil at the same time, the Lord lets the first of these pairings occur. He does so not from intent but from an inability to prevent it because of the ultimate goal, which is our salvation. It is because of these two factors--our ability to be engaged in something evil and something true at the same time, and the Lord's inability to prevent this because of the goal, which is our salvation--that our discernment can be lifted up into heaven's light and see what is true or recognize it when we hear it even while our love remains down below. This means that we can be in heaven in our discernment and in hell in our love; and we cannot be denied this possibility because we cannot be deprived of the two abilities that make us human and distinguish us from the beasts, the two abilities that alone make our rebirth and salvation possible, namely, our rationality and our freedom. These two abilities, that is, are what enable us to act in keeping with wisdom or to act in keeping with a love that has no wisdom. These are what enable us to look down from wisdom on our love below and therefore see our thoughts, intentions, and feelings, to see what is evil and false and what is good and true in our life and our beliefs. If we could not recognize and admit these things in ourselves, we could not be remade. I have already discussed these abilities [15] and will have more to say about them later [71-99].

This is how we can be engaged in what is good and what is true together and in what is evil and what is false together, and do this alternately.