In Biblical terminology, you need to genuinely
believe (trust, have faith) in Jesus. God will judge people according to their hearts. The Bible isn't clear on the minimum to be saved, because God's call is for people to devote themselves to him, not how they can squeak past punishment. If one thinks he is saved, but is not at least genuinely thankful to God for it, then they may actually have saving faith.
As a result of the Bible not clearly stating the minimum to be saved, humans have come up with lots of attempts to describe
exactly what the
minimum is to be saved is, but the detailed arguments need not necessarily be exactly the same for each person. God will judge people according to their hearts, not which pieces of information are in their minds. e.g., does one need to believe that God, the Father raised Jesus, the Son of God from the dead to be saved?
Here's the way I describe the "minimum," although as I said, only being interested in the minimum or examining the minimum might not be sufficient. In James chapter 2, James describes two kinds of faith ("faith" and "dead faith"). Saving faith always results in actions according to that faith. These two kinds of faith are applicable to more than just salvation.
If I tell you a meteor is going to crash into your office in the next few minutes, you probably wouldn't believe me. If you then saw an article on an Internet web site that a meteor was about to crash within a block of you, your faith that it wasn't going to happen might be shaken up. If you heard the local warning sirens and police using bullhorns to tell people to evacuate, you might believe the meteor was coming, but "who could really know if it was going to hit your office?" If three of your friends were at the window and said they could see the meteor and it was headed right at the window but a shower of dust prevented you from seeing the meteor for yourself, you would probably believe them enough to act on that information immediately. Only the last one is saving faith. The point is, you reached a point of genuine belief the meteor would hit your office, and as a result you acted on it—and it had nothing to do with the action you did or didn't take (leaving the building or not). At the end of every day, you leave the building, but on those other days leaving the building had nothing to do with faith about a meteor. What matters is what the faith was like in your heart about the meteor coming.
One way to describe the absolute minimum requirements is that one must:
- Believe God is real
- Believe that God sent his Son, Jesus, the Christ to pay the penalty of our sins for us
- Believe God is GOD (has the right to tell us what is right and wrong and to hold us accountable)
- Accept God as one's GOD (yield to this Lordship and thus, his commands)
Having saving faith in these will always result in a person taking action from their heart (not because they think they're "supposed" to take action).
Beyond these basic points, it matters who you ask, but more importantly it matters what the context is in which you are asking. The salvation message could include other (also important) things. Does the person believe we have all done wrong and have no way to pay for our wrongs (we can't change what we did in the past)? Does a person need to believe what God said in the Bible, such as God, the Father raised Jesus from the dead?
A person who has genuinely believed is saved, but he won't know he is saved. The desire to know one's Lord better is the result of genuine salvation. The pursuit to know about God more (and know him better personally) will raise questions in a person's heart and mind about what God asserts in the Bible. After
understanding what God said,
believing (the kind that turns into actions) what he said will grow the person's faith. Eventually there will be enough faith that a person knows they are saved. Doubts
will arise along the way. How one handles those doubts matters a huge amount. The person either chooses to keep moving forward in believing (and looks for evidence) or stalls or turns away. No one but God knows without a doubt when a person is actually saved.
Some will say that they want to believe, but just don't. Everyone starts out that way in some fashion. Believing the truth about God is a gift that God grants. Such people need to ask God to grant them to believe in the truth about him. If it is genuinely true that they want to believe, then they will start doing what God said: be obedient (which includes learning what it means to be obedient). It is not the obedience which saves, but God grants faith in response to our efforts to do what we think God wants rather than what we want (i.e., obedience).