For we are not contending against flesh and blood, but against the principalities, against the powers, against the world rulers of this present darkness, against the spiritual hosts of wickedness in the heavenly places. Perhaps we modern Christians have ignored the Bible's testimony about the pernicious, seductive and evil character of the opposition party. Our 'goods' can so easily become our ' gods'. There is a profound truth in the power of evil, against which Christ calls us to 'stand watch'. One may bring one's heart to pray, but the difficulty is in keeping one's heart there.
Spirituality is the key to keeping 'warmed up' for the fight against sin, the world and the devil.
One of the greatest writers about the power of evil is C. S. Lewis. If you have never read his Screwtape Letters, you have missed a real treat. Lewis shows the banality of evil and the way the Enemy uses ordinary things to make faith distasteful and to be avoided. The premise of the book is that Screwtape is teaching 'Wormwood', a young devil who is trying to lead astray a new convert. And Screwtape urges Wormwood to get his 'convert' to look critically at his fellow worshippers when he goes to church.