After hearing the word one must believe in Jesus as the Son of God. This is a concept which is widely misunderstood in the religious world (in my opinion). What does it mean to believe? For the purpose of reviewing the plan of salvation we need to introduce the concept of Biblical Belief. Please follow the link provided for an in-depth study of this important topic.
"Believe": The Greek word translated "believe" in the gospels and in the book of Acts is pisteuo. Vine's notes that pisteuo "signifies, in this sense of the word, reliance upon, not mere credence."
Merriam-Webster includes the ideas of thinking or supposing in the definition of believe. How do you think most religious persons view belief? Do they hold an opinion that Jesus is the Son of God, or do they apply the Biblical definition and live their lives only for Him? A Methodist church close to my home recently displayed a sign stating "All who believe in Jesus have eternal life." The statement "all who believe" would lead one to think they included those who placed such a degree of faith in Jesus that they are willing to suffer shame for His name along with those who merely held an opinion that the world was unlikely to have come into being without some higher power. Is this valid? Will the devils spend eternity in heaven? James states they also believe, and tremble! Biblical Belief is a firm conviction in the truth and application of its teachings to ones life, not a superficial supposition or credence that something is true. Belief is absolutely essential to salvation. After hearing the word preached by Philip the Ethiopian eunuch asked him "See, here is water. What hindereth me from being baptized?" Philip responds by telling him "If you believe with all your heart, you may." Notice the eunuch's response in verse 37. He affirmed his faith in Jesus as the Son of God prior to his baptism. To review the first step leading to salvation (hear the word), how did the eunuch learn what was necessary for his salvation? There was an angel involved, but did he reveal to the eunuch what was necessary for salvation? No! The angel led Philip to the eunuch and placed the responsibility of telling the eunuch what he must do into Philip's hands. In the great commission Jesus placed the responsibility for teaching others into the hands of His disciples. So, just as the eunuch heard the word from another man, people today must hear from another man. The word will not be revealed to them by an angel or other spiritual being.