The age old question was once asked by a simple jailer:

“Sirs, what must I do to be saved?” Acts 16:30

His prisoners (the Apostle Paul and his companion Silas) responded with confidence, clarity, and boldness:

They replied, “Believe in the Lord Jesus, and you will be saved—you and your household.” Acts 16:31

This sums up the message Christians are proclaiming to the world: sinners are saved through faith in Christ alone. But what does the Bible mean when it speaks of trust, belief, or faith? What does it mean to believe in Jesus or put your faith in Christ? Theologian Wayne Grudem sums up the Biblical teaching well in a few short sentences:

When a person comes to trust in Christ, (these) three elements must be present. There must be some basic knowledge or understanding of the facts of the gospel.

There must also be…agreement with these facts. Such agreement includes a conviction that the facts spoken of the gospel are true, especially the fact that I am a sinner in need of salvation and that Christ alone has paid the penalty for my sin and offers salvation to me. It also includes an awareness that I need to trust in Christ for salvation and that He is the Only way to God, and the only means provided for my salvation. This approval of the facts of the gospel will also involve a desire to be saved through Christ.

But all this still does not add up to true saving faith. That comes only when I make a decision of my will to depend on, or put my trust in, Christ as my savior. This personal decision to place my trust in Christ is something done in my heart, the central faculty of my entire being that makes commitments for me as a whole person. (Systematic Theology, p. 712)

There you have the three necessary elements of true saving faith: knowledge, agreement, and trust. Without these, there is no true faith. In order to be saved, one must know the basic truth of the gospel (and the basic truths therein), agree to them, and trust in Christ as their Savior and Lord.

So, do you know the gospel?

Do you agree to the truths of the gospel?

Have you trusted in Jesus alone to save you from your sin?