Why does God allow the Devil to exist? Why should he have fallen? Why should God have allowed our first parents to fall, and in their fall to drag down the whole human race? These questions were forced upon me, and distressed me, when young in the Christian faith. I had to learn to trust God where I did not understand. I had to learn as a start of all true learning, the concept of God as supreme, all-wise, all-loving, absolutely righteous and holy in all His ways.
In cases where we cannot understand, we may well believe that if we had the full knowledge of the case as God has, and were possessed of the wisdom and power of God, and were called upon to act, we should act exactly as God has acted.
There is a very great distinction between man and the lower creation. The lower creation is not responsible. Their lives are purely animal, governed by instinct, and therefore without responsibility. Man, the highest creation of God on this earth, was created with a will, and therefore carrying with it responsibility, and capable of communing with his Creator. If God had created man in such wise that he were unable to depart from the path of dependence and obedience, He would have created mere automatons, will-less creatures, with no power of choice. Man so created would have been merely a superior animal with no responsibility attaching to him. We shrink from the thought of such a creation as unworthy of God, and entailing terrible loss to mankind.
We have to learn to look at circumstances in the light of our knowledge of God, and not decide on the character of God in the light of circumstances, as we see them, or think we see them.
The God, who could produce such characters as Job, Abraham, Moses, David, Isaiah, in the Old Testament times, and Paul, Peter, James, John, in New Testament times is a God, we can trust through and through.
The mystery of Satan, and the condition of the world around us, may yet be known by us when we see light in God's light in the coming day of manifestation. Till then let us trust our God implicitly, and never question any of His ways.