What is the Salvation of God and why must you have it to enter Heaven?

“If you think you’re going to heaven, but heaven does not influence the way that you think, you had better rethink that thought. ”
Matthew Maher

Revelation 21:27
²⁷ But nothing unclean will ever enter it, nor anyone who does what is detestable or false, but only those whose names are written in the Lamb’s book of life.

In a nutshell, salvation is returning a relationship between God and man to what it was before Adam sinned and brought the curse of death onto all of mankind.

Adam and Eve did not realize the horrors of sin and death and therefore ate the forbidden fruit God clearly stated they should not eat or they would die!  Today, man does not realize the awesome gift of restoration that Jesus Christ offers as he died in our place on the cross. He paid a debt He did not owe because we owed a debt we could not pay for – our sin.

James 2:10
Whoever keeps the whole law but stumbles at just one point is guilty of breaking all of it.

The scene in the video below and the 2 audio files are speaking about the bible from John Chapter 3 when Jesus meets with Nicodemus secretly in the night. Nicodemus was the chief religious leader of his day above all the scribes, Sanhedrin Sadducees and all other pharisees. The numbers filters from thousands to hundreds to dozens to Nicodemus. This is important because not even the chief of all the Jewish religion knew what Jesus was about to say and offer him.

John Chapter 3
¹⁶ For God so loved the world that He gave His one and only Son, that everyone who believes in Him shall not perish but have eternal life.
¹⁷ For God did not send His Son into the world to condemn the world, but to save the world through Him.
¹⁸ Whoever believes in Him is not condemned, but whoever does not believe has already been condemned, because he has not believed in the name of God’s one and only Son.

Romans 10
⁸ But what does it say? “The word is near you; it is in your mouth and in your heart,” that is, the message concerning faith that we proclaim: ⁹ If you declare with your mouth, “Jesus is Lord,” and believe in your heart that God raised him from the dead, you will be saved. ¹⁰ For it is with your heart that you believe and are justified, and it is with your mouth that you profess your faith and are saved. ¹¹ As Scripture says, “Anyone who believes in him will never be put to shame.” ¹² For there is no difference between Jew and Gentile—the same Lord is Lord of all and richly blesses all who call on him, ¹³ for, “Everyone who calls on the name of the Lord will be saved.”
¹⁴ How, then, can they call on the one they have not believed in? And how can they believe in the one of whom they have not heard? And how can they hear without someone preaching to them? ¹⁵ And how can anyone preach unless they are sent? As it is written: “How beautiful are the feet of those who bring good news!”
¹⁶ But not all the Israelites accepted the good news. For Isaiah says, “Lord, who has believed our message?” ¹⁷ Consequently, faith comes from hearing the message, and the message is heard through the word about Christ. ¹⁸ But I ask: Did they not hear? Of course, they did:  “Their voice has gone out into all the earth, their words to the ends of the world.”