You believe that there is one God. You do well. Even the demons believe—and tremble!
There are many people who think it’s enough to say they believe in God. I have heard many times people say the phrase “I believe in God,” but they know not clearly define the God in whom they say that they believe. The reason is they say they believe in God but they do not know Him. And they do not know because they have not established a relationship with God. Even the demons believe in God and are subjected to Him to the point that they tremble at His presence. So it is not enough merely to say that we believe in God.
The Bible says very little about “believing in God,” instead, is more frequently found believing in Jesus, the Son. When we believe in Jesus Christ, the Son of God, we also believe in His Father. That says the Lord Himself in John 12:44-45: Then Jesus cried out and said, “He who believes in Me, believes not in Me but in Him who sent Me. And he who sees Me sees Him who sent Me.” Jesus is the visible image of the invisible God, who sent His Son to die on a cross as a ransom for all sinful humanity.
As James 2:19 says, anyone, even the demons believe in God. Believing in God is to accept His existence. As such, only those who call themselves atheists or agnostics refuse to accept that God exists. Therefore, if it was enough just to believe in God, only those who reject His existence were at fault. However, in light of what James says, it is obvious that if so, demons would be considered believers, which we know is not true.
Rather than believe in God, the Bible speaks of trusting in God. An example is found in Jeremiah 17:7-8: Blessed is the man who trusts in the Lord, and whose hope is the Lord. For he shall be like a tree planted by the waters, which spreads out its roots by the river, and will not fear when heat comes; but its leaf will be green, and will not be anxious in the year of drought, nor will cease from yielding fruit. Trusting in God is the same as believing in His words.
Then the root of the issue is not simply believing in God but believe God. Any being, whether human or spiritual could believe in God; but believe God means more than that. God certainly will feel more offended with those who do not believe in His words that with those who deny His existence. Not believing in God, as do an atheist is to ignore that He exists; but do not believe God is telling liar is doubt His faithfulness, His seriousness and integrity.
The Bible is full of promises for those who have chosen to believe in God. Just read Psalm 23 we realize some of them: we will lack nothing, He makes us relax, He shepherds us, He comforts the soul, He takes away the fear, He is always with us, He is inspirational, He supplies us with food, He anoints us, His good and His mercy follow us and we dwell in His house for eternity. In many other places in the Bible there are so many promises of Heavenly Father.
Now I say to you who say that believe in God, why you not believe God? Why do you refuse to believe that you are saved by grace? Why did you legs tremble before the shortage? Why are you anxious and tired? Why do you walk with fear? Why do you say that you are alone? Why are you discouraged? Why are you saying that things are bad? No offense to God with your disbelief to His promises. Do not think that atheists are worse than you because when one only believes in Him and does not believe to Him, he is in the same place where the demons are. God bless you.