You have to believe, and obey the gospel to be saved.
What is the gospel (i.e. the good news)?
The gospel:
The gospel is believing Christ died for our sins, believing He was buried, and that He rose again on the third day (according to the Scriptures). But we also have to obey the gospel (according to Scripture), too.
What is obeying the gospel (i.e. the good news)?
Well, the Bible refers to three places about “not obeying the gospel.” All three places within the Bible that talk about “not obeying the gospel” are used in an unfavorable light. For they refer to the Lord condemning anyone who does not “obey the gospel” (Romans 10:16) (2 Thessalonians 1:8) (1 Peter 4:17). In fact, if you were to stop and think for a moment, “obeying” is different than “believing.” Therefore, one must also obey the gospel and not just believe it alone. Can this line of thinking be supported with Scripture? Yes, absolutely.
Examples of “obedience to the faith” (Romans 16:26) can be seen in Hebrews 11 (Which is the great hall of faith chapter of God’s people). What is interesting is that this chapter is not about uplifting how men of God can sin and still be saved, but is about uplifting men of God obeying God after they had believed. This makes sense because James says he will show you his faith by his works (James 2:18). This is not about just doing good works while a believer also sins while they have a belief on Jesus. For Jesus did not accept those believers who did wonderful works and yet they also worked sin or iniquity (See: Matthew 7:23). For without holiness, no man shall see the Lord (Hebrews 12:14).
Note on 1 Thessalonians 1:8: Those who do not know God do not keep his commandments; For that person who says they knows the Lord and does not keep his commandments is a liar and the truth is not in them (See 1 John 2:4).
We know the gospel is believing in Christ’s death and resurrection (1 Corinthians 15:1-4) (1 Corinthians 15:11) (Romans 1:16).
But obeying is clearly different than simply believing. A place where we see in the Bible an example of obeying the gospel is in Romans chapter 6.
We can obey the “death of Christ” aspect of the gospel:
Verse 4 talks about how we are buried into Christ’s death by baptism.
This is “spirit baptism” (verses 3-4) (i.e. being baptized into the Spirit). How so? Well, there is one baptism (Ephesians 4:5), and being “spirit baptized” into Jesus Christ can be seen in Acts of the Apostles 19:1-6 with Paul baptizing (in the name of Jesus) certain disciples in Ephesus by the laying on of hands (and not by water baptism). We also learn that accepting the gospel can also lead to one being spirit baptized (See Acts of the Apostles 10:42-45). Acts of the Apostles 3:19 says “repent and be converted.” (Note: Repentance is seeking forgiveness of one’s sins with the Lord; See: Matthew 3:6, Matthew 3:8, Mark 1:4-5, Acts of the Apostles 8:22, etc.). This means that if a person comes to the Lord for the first time they are converted or given a new heart with new desires (i.e. we are born again spiritually) and in many cases they can receive the Holy Ghost as a gift at this point. Verse 5 talks about this spirit baptism as being planted together in the likeness of his death. Verse 6 says that the old man is crucified with him that the body of sin might be destroyed.
Seeking God’s mercy is at the heart of putting away unrighteousness. For it is written: “If we confess our sins, he is faithful and just to forgive us our sins and to cleanse us from all unrighteousness” (1 John 1:9).
We can obey the “resurrection of Christ” aspect of the gospel:
So as Christ was raise from the dead, so we must also should walk in newness of life. Is this essential to salvation? Yes.
Romans 8:13 says,
“For if you live according to the flesh, you will die; but if by the Spirit you put to death the misdeeds of the body, you will live.”