Jesus gave to Peter the keys of the kingdom (Matthew 16:19). On the day of Pentecost he began to use them to unlock doors.
But Peter said two things that might be taken as contradictory. First, in order to explain the supernatural phenomenon that occurred he quoted Joel, predicting the Last Days and ending with a simple invitation, “’And it shall come to pass that everyone who calls upon the name of the Lord shall be saved.’” (Acts 2:21 ESV)
But second, when the Spirit convicted the people of their sins they cried out, “What shall we do?”
“And Peter said to them, ‘Repent and be baptized every one of you in the name of Jesus Christ for the forgiveness of your sins, and you will receive the gift of the Holy Spirit.’” (Acts 2:38 ESV)
Is there one key or are there more?
In the history of the Church there has been confusion over what God requires for salvation. Some say there are no “works” at all but that God chooses the ones who might be saved and moves upon them to that end by an irresistible grace. Others sing, “Only believe, only believe, all things are possible, only believe.” Some Churches have developed relatively elaborate systems of doctrine, morals, ritual, spirituality, and ecclesiastical government to fulfill every jot and tittle of the law. So today, Christianity is divided between factions over how salvation is accomplished. These are honest disagreements because Scripture is not self-explanatory. Various groups have proof texts for the position that they hold.
However, we cannot all be correct. If the Spirit inspired the sacred writings then passages do not conflict with each other and apparent discrepancies point to a lack of understanding on the part of us fallible human beings. But why should we care?
John Ankerberg once famously said, “If one tries to be saved in a way that one cannot be saved then one will not be saved.” Of course, by saying that Ankerberg melodramatically raised the stakes so that folk might take his perspective more seriously. But according to Romans 2:12-16, God will judge us justly according to the truth that we have.
Be that as it may, what if sincere Christians want a better grasp of the keys? What if Christian teachers want to be more accurate in explaining the word? What if we desire to attain to the unity of the faith and knowledge of the Son of God? What if God’s power is unlocked by a better understanding of his purpose?
Assuming those positive motivations, I would like to put forth this theory: the simpler formulas summarize and include the more complex ones; otherwise, one makes hundreds of Biblical verses optional and the temptation to sin might prevent the needed “obedience of the faith” that saves (Romans 1:5 and 16:26). Therefore, we should reject de minimis gospels and rather observe all that the Lord has commanded us.