You can believe in a lot of things. You can believe that a certain sports team is the best or that something you heard is true. In the same way, you can believe God is real. You can believe Jesus lived on Earth and that the stories of the Bible are true—but that is not the same thing as trusting in Jesus.
Many believe that God exists, but they do not have a personal relationship with Him. James 2:19 says, “You believe that there is one God. You do well. Even the demons believe…” Satan knows that God is real. The demons believe in Jesus and His Lordship—but they do not have an active, personal relationship with Him.
The difference between belief and trust is in the action involved in trusting. You can believe something one day and then change your mind the next. But to put your trust in something—to have faith in something—is to commit to aligning your actions with your belief. As Pastor Adrian Rogers would say, “Faith is belief with legs on it.” God gave us His Son, His Word, and His Holy Spirit not just so that we could know about Him, but so that we could know Him personally. Have you put your trust in Jesus, or have you settled for mere belief?