The sinner’s prayer can indeed and often has been sincerely used to express the faith and repentance of the covert. However, the sinner’s prayer is not some mystical spiritual formula which secures salvation upon utterance. Our Lord knows the heart of all, and no mind is hidden from him (Heb 4:13).
The Lord is not slow to fulfill his promise as some count slowness, but is patient toward you, not wishing that any should perish, but that all should reach repentance (2 Peter 3:9). According to Peter here, the desire of God is not that we should perish, but that we might repent. So here we see the opposite of “to perish” is found through repentance. Unlike formulaic prayer, repentance is impossible outside of sincerity.
So, what must we do to be saved? That is, what must we do to have new life in Christ? Then he brought them out and said, “Sirs, what must I do to be saved?” And they said, “Believe in the Lord Jesus, and you will be saved, you and your household.” And they spoke the word of the Lord to him and to all who were in his house. And he took them the same hour of the night and washed their wounds; and he was baptized at once, he and all his family. Then he brought them up into his house and set food before them. And he rejoiced along with his entire household that he had believed in God (Acts 16:30-34).
So, what must we do? Believe? Indeed! But we must understand what we are saying when we say we must believe. The Greek word used here is Pisteuson (Πίστευσον).
Luke has another passage in which we see this word used: While he was still speaking, someone from the ruler’s house came and said, “Your daughter is dead; do not trouble the Teacher any more.” But Jesus on hearing this answered him, “Do not fear; only believe, and she will be well” (Luke 8:49-50). We can understand from this exchange that Jesus is not asking Jairus to simply change his way of thinking from positive to negative, as if He was saying, “Deny the fact that you heard that your little girl is dead and convince yourself she is alive!” No! Rather, Jesus is telling Jairus to trust in HIS word over and above all things—to rely on Him, to place his hope and faith in Him even in the face of death. How far beyond intellectual agreement this is!
And so we must again look at our question. “Does the Bible say we have to pray to be saved (as in the sinner’s prayer) or just believe?”
Believe, yes. But not “just” (as we sometimes use the word “just”) believe. “Believe” encompasses all that we are. So much so that we cannot on our own believe as we are called to. Belief unto salvation is not accomplished through force of will or depth of conviction, but through God-given faith enabled by the grace of God and the work of the Holy Spirit. For it is by grace you have been saved, through faith—and this is not from yourselves, it is the gift of God—not by works, so that no one can boast (Eph. 2:8-9).
Grace and peace to you through Jesus Christ our Lord.
Pastor Brian Torres