If there had been no redemption by the Lord, injustice and malice would have spread throughout the Christian realm in both worlds (the earthly and the spiritual).
There are many reasons for this. One is that all human beings after death come into the world of spirits. They are exactly the same then as they were before. When they first enter that world, none of them can be prevented from interacting with parents, siblings, relatives, and friends who have died. At that time every husband first looks for his wife and every wife looks for her husband. Their spouses as well as their family and friends introduce them into various social groups that include people who are outwardly like sheep but are inwardly like wolves. The newcomers are corrupted by these wolves—even the newcomers who have been particularly devoted to religion. Because of this, and also because of horrible practices that are unknown in the physical world, that world is as full of malicious people as a pond is green with frogs’ eggs.
Interaction with evil people there has this full of malicious people, as you can clearly see from the following similar situations: As you spend time with thieves or pirates you eventually become like them. As you live among adulterous men and promiscuous women, eventually you think nothing of adultery. If you join a rebel group, eventually you think nothing of doing violence to anyone.
All evils are contagious. They are like a plague you become infected with just by breathing in and out. They are like cancer and gangrene that spread and corrupt nearby areas, then more and more remote areas, until the whole body dies. The cause: from birth we all enjoy evil.
From the points made just now it can be clear that if the Lord had not brought about redemption, no human being could have been saved and no angels could have continued to exist in their state of integrity.
The sole and only direction in which to run for refuge is to the Lord, or else we perish. He says,
Live in me and I [shall live] in you. Just as a branch cannot bear fruit by itself unless it lives in the vine, the same goes for you unless you live in me. I am the vine. You are the branches. Those who live in me and I in them bear much fruit. For without me you can do nothing. If any do not live in me, they are cast out. Once dried they are thrown into the fire and burned. (John 15:4, 5, 6)
from True Christianity, Volume 1, Section 120