I read an article on (a well known Christian news site) that reports as many as 58% of Christians don’t believe either the devil or the Holy Spirit really exist as actual persons. I had always thought that believing in the Trinity was necessary for salvation. Am I wrong?
Although the Bible makes a strong circumstantial case for the Trinity, the only requirement for salvation is that we believe Jesus died for our sins and rose again. Of course even a cursory study of theology shows that only a sinless man could do that, and only God is sinless.
My biggest problem in this matter is that Christians have the Holy Spirit sealed within them, guiding, advising, and empowering them. And only the Holy Spirit can make it possible for us to understand the things of God (1 Cor. 2:14). How can you take advice and receive power from Someone you don’t believe in? How can you say you believe God’s Word if you don’t believe in the only One who can help you understand it? No wonder the Church has become so weak. Like Paul said, these people have a form of godliness but deny its power (2 Tim. 3:5).
And as for Satan, the Bible calls him the prince of this world (John 14:30) and the god of this age (2 Cor. 4:3-4). John wrote that the whole world is under the control of the evil one (1 John 5:19). These verses all speak of a living being, not just a malevolent force. People who refuse to acknowledge the existence of Satan have no one left to blame for the evil in this world but God. This is a position that I imagine will be quite uncomfortable for them when they stand before Him and are asked to explain themselves.