"So faith comes from hearing, that is, hearing the Good News about Christ." Romans 10:17 (NLT)
This verse has been misinterpreted many times. Many people have used it to say that to grow your faith, just keep exposing yourself to the Word. But that is only a half-truth. The religious leaders of Jesus' day - the Pharisees - knew God's Word inside and out, and yet Jesus chided them as unspiritual and ignorant of God's will. He said to them, "You search the Scriptures because you think they give you eternal life. But the Scriptures point to me!" (John 5:39).
Jesus was teaching them and us that Bible knowledge alone doesn't lead to eternal life, but a genuine encounter and ongoing relationship with Him does. Eternal life and transformation don't come about by some ethereal force but through a person, the God-man Jesus Christ. He says that He gives eternal life. Our belief alone doesn't save us, but when we demonstrate a genuine faith that Jesus died for our sins and Go (an action proving genuine faith) to Him for forgiveness, then we are saved. He does the saving, we simply believe by going to Him for forgiveness of sins and receiving eternal life.
I encourage you to read this whole chapter on your own to learn what is being said in the context. Paul is saying that the only way to be saved is by putting one's faith in Jesus ONLY. The Jews of Paul's day thought it was "good works", but Paul is teaching them that Jesus alone saves and faith in Him is the means by which this salvation occurs. No other god, or belief system can wash away our sins and make us new. Only Jesus can do that.
Let's sum it up this way - eternal life doesn't come from our efforts, but by faith, and that faith must be in the work of Jesus Christ and what He did for us on the cross, and what He will do by His transforming Spirit when we call on Him to be saved.
The only way people will find out about this "Good News" is if we, His followers, tell them about Jesus and what He has done for us. Our testimony of Jesus will give people the chance to encounter Him and put their trust in Him for salvation. When they hear about Him, then and only then, will they have the opportunity to put their faith in His saving power and love. TELL so others may HEAR.