British preacher Martyn Lloyd-Jones explained that Christians' ignorance of our chief antagonist can lead to serious but unnecessary difficulties. It can cause us great personal pain. It can cause us to confuse flesh and spirit. Ignorance of Satan and his devices can cause the church to operate on the basis of a false zeal.

Sadly, Christians often build their doctrine of Satan on some foundation other than the Bible — superstition, untrustworthy personal experience, how-to books that aren't grounded in the Word, Halloween caricatures, or the unbelieving world's television and movie portrayals. Many Christians simply ignore the subject altogether. Regardless of its cause, ignorance of Satan and his devices gives the enemy the advantage (2 Corinthians 2:11).

The only proper way to understand Satan is to understand what the Bible says about him. When properly understood, Lloyd-Jones asserts, the doctrine of Satan can be "a comforting and releasing doctrine" for the Christian:

In addition to those [angelic] beings who help us and care for us, there are others who are our greatest enemies. They are opposed to us and set against us, and obviously, therefore, we must consider the teaching of the Bible concerning them. There are many reasons for doing that. It is quite impossible to understand human history without considering what the Bible has to tell us about these fallen or evil angels. We cannot hope to understand man as he is today, we cannot hope to understand the world, apart from this. And it increasingly seems to me that the essence of the error which most people seem to make [in our time]...is that they fail to consider the Biblical doctrine of the devil and his angels.

But it is also a most practical doctrine from the standpoint of the individual Christian's experience. I find more and more in my pastoral experience, as I am privileged to interview people, and to help them in their personal fight of faith, and in their personal problems, that the essence of the trouble is that such people have not realized the powers that are set against them. So often I have to deal with people who have been sent to a psychologist, a psychoanalyst, or somebody like that, and whose problem very frequently is quite simply that they have without realizing it been besieged and attacked by the devil.¹ And the essence of the treatment, and of the cure, is to enlighten them with respect to this; to make them see that what they have attributed to themselves and their personal sin and failure (perhaps even mental disease), is really to be attributed only to the mighty antagonist who is described in the Bible as the devil. So that, strange though it may sound, to understand the Biblical doctrine of the devil and his angels can be a most comforting and releasing doctrine.

So then let us look at it as it is unfolded to us in the Scriptures, and we start at once with the one who is described as the devil. Here is one to whom reference is made in the Bible from the very beginning to the end, from Genesis to Revelation. Constantly, running right through, there are references to the devil and his captives....[W]e need to ask why it is that those of us who are evangelical Christians so infrequently study this doctrine and fail to give it its due place and attention in our Christian life. I maintain seriously that it is our failure at this point that surely must account for many of the pitfalls into which we fall so readily, not only in our personal experiences, but in our evangelism, and in many other respects. For if the devil can but keep us asleep, he will fill us with a false zeal, causing us to confuse the flesh and the spirit, and thus when we appear to be most zealous we can unwittingly be most under the influence of the enemy.² 

Next: What is Satan's Origin?

References:

1. Before being called to the ministry, Lloyd-Jones himself was a respected medical doctor.

2. D. Martyn Lloyd-Jones, Great Doctrines of the Bible (Wheaton, Illinois: Crossway Books, 2003), 115-16.