Satan - Billy Graham

"To Jesus and the apostles Satan was very real. He was called "the prince of this world," "the god of this age," and "the prince of the power of the air." The names used concerning him indicate something of his character and strategy. He was called "deceiver," "liar," "murderer," "accuser," "tempter," "destroyer," and many other such names.  The Apostle Paul said he wanted to visit the church of Thessalonica "but Satan hindered us" (I Thessalonians 2:18). Thus the evangelist and the work of evangelism is opposed on every hand by tremendous spiritual forces."

"Satan's greatest strategy is deception. His most successful strategy has been to get modern theologians to deny his existence...If we ignore the existence of Satan or our ignorance of his devices, then we fall into his clever trap. However, we have the glorious promise that: 'Greater is He that is in us than he that is in the world.'"
Billy Graham
"Why the Berlin Congress?", World Congress on Evangelism, Berlin, 1966