When we ask people to believe on Christ for their salvation, we are asking them to trust in Christ alone to save them.
Here is an illustration I have always found helpful. It is one Billy Graham enjoyed using.
An interesting incident took place at Niagara Falls. A crowd watched as a man rolled a wheelbarrow filled with two hundred pounds of dirt across a tightrope suspending over the Falls. Once accomplished, the man asked the spectators, “How many of you believe I can roll a man across?”
One, with a great deal of excitement, said, “I know you can do it.”
The man looked at him and said, “All right, you’re first!”
The man fled. He may have accepted it as true the man could do it, but he did not trust him to do it.
Accepting it as true that Jesus Christ is your only way to heaven, you must trust in Him alone to save you and recognize that He and He alone can get you to heaven.