What must I do to be saved?
Glad you asked:
A crisis that threatened a Philippian jailer with death prompted him to ask Paul and Silas the most important question in life: “What must I do to be saved?” (ACTS 16:30) The reply of Paul and Silas was this: “Believe in the Lord Jesus.” (ACTS 16:31) This is God's requirement for salvation in a nutshell. Jesus Himself expressed GRFS even more succinctly using three, four and five letter words: “Ask… seek… knock…” (MT 7:7). As Hebrews 11:6 states: “he [God] rewards those who earnestly seek him” (cf. IS 45:19). Seeking God is the beginning of saving faith, and not seeking God or rejecting His salvation in Christ is the essence of evil atheism or faith in I-dolatry (RM 3:11, 1:18-23).
I like to denote GRFS by the use of the Greek word kerygma, meaning proclamation or preaching, referring to the good news (Gospel) concerning salvation to heaven and from a just hell (the DOD, cf. RM 1:16, GL 1:6-12, CL 1:21-23). This Gospel was preached by Peter (in ACTS 2:22-24) and summarized by Paul (in 1CR 15:1-8). The salient points include: Jesus was a man, accredited by God (to be Messiah), who died on a cross, but who was raised or resurrected from the dead. Messiah is the Way to heaven.
The normative way of stating the kerygma/GRFS in the NT is “Accept Christ Jesus as Lord” (as in 2CR 4:5 & CL 2:6). The main points of Christian orthodoxy implicit in this statement can be explained or elaborated as follows:
1. There is a/one all-loving and just Lord or God (DT 6:4, JN 3:16, 2THS 1:6), who is both able (2TM 1:12) and willing (1TM 2:3-4) to provide all morally accountable human beings salvation or heaven—a wonderful life full of love, joy and peace forever.
2. Human beings are selfish or sinful (RM 3:23, 2TM 3:2-4, CL 3:5), miserable (GL 5:19-21), and hopeless (EPH 2:12) or hell-bound at the judgment (MT 23:33 & 25:46) when they reject God’s salvation (JN 3:18, RM 2:5-11).
3. Jesus is God’s Messiah/Christ and incarnate Son, the way that God has chosen (JN 3:16, ACTS 16:30-31, PHP 2:9-11) of providing salvation by means of his atoning death on the cross for the payment of the penalty for the sins of humanity (RM 3:22-25 & 5:9-11), followed by his resurrection to reign in heaven (1CR 15:14-28).
4. Thus, every person who hears the NT Gospel needs to repent and accept God’s justification in Jesus as Christ/Messiah the Lord or Supreme Commander (LK 2:11, JN 14:6, ACTS 16:31), which means trying to obey His commandment to love one another (MT 22:37-40, JN 13:35, RM 13:9)—forever (MT 10:22, PS 113:2).
5. Then God’s Holy Spirit will establish a saving relationship with those who freely accept Him (RV 3:20) that will eventually achieve heaven when by means of persevering in learning Truth/God’s Word/sanctification everyone cooperates fully with His will (JN 14:6, 17&26, RM 8:6-17, GL 6:7-9, EPH 1:13-14, HB 10:36, 12:1, JM 1:2-4).
The kerygma or GRFS can be stated in various ways, which may cause confusion. Some statements (e.g. ACTS 16:31, quoted previously, & EPH 2:8-9) are in terms of believing right, and others (e.g. MT 7:21, “only he who does the will of my Father will enter heaven”, cf. GL 6:7-9 & EPH 2:10) are in terms of behaving right. This prompts the question: Is salvation obtained by believing God’s words or by doing God’s works? The answer is indicated by John 6:29: “The work of God is to believe in the one [Messiah/Christ] He has sent.” This implies that believing and willing are essentially synonymous.