Do you know what is purpose son of God birth and death?

All your material things in this world will be gone and only the best story will remain and remembered for a while. and only God love is eternal. That is what the Bible said.

The Father, the Son and the Holy Spirit had a plan of salvation all worked out before anything material was created (see Revelation 13:8 and Ephesians 1:4). Then, after sin began to corrupt this earthly creation, God started to show how that would be put right. The first clue is in Genesis 3:15, and the final outcome is in the last book of the Bible, Revelation.

The Son of God agreed to leave Heaven and the Godhead, to be born of the virgin Mary, to become a sinless man who would bear God's judgment on all sin. That is why Jesus had to die on the cross and then be resurrected, which proved Him to be the Son of God. Here is the explanation of God's purpose in connection with the Son:

"But now the righteousness of God without the law is manifested, being witnessed by the law and the prophets; even the righteousness of God by faith of Jesus Christ unto all and upon all them that believe. For all have sinned and come short of the glory of God, being justified freely by his grace through the redemption that is in Jesus Christ; whom God has set forth. Jesus Christ is propitiation through faith in his blood, to declare his righteousness for the remission of sins that are past, through the forbearance of God; To declare at this time his righteousness, that he might be just, and the justifier of him which believes in Jesus...For when we were yet without strength, in due time Christ died for the ungodly."

That's in the Bible book of Romans, chapters 3 to 5. Please get a Bible and start studying it. All the answers to your many Qs about God the Father, and the Son of God, and in there. It's all about eventual cosmic justification of God's righteousness. "There is no-one righteous, not even one" the Bible states, but Romans 1:16-17 says that "the gospel of Christ is the power of God unto salvation to every one that believes... For therein is the righteousness of God revealed from faith to faith, as it is written, 'The just shall live by faith'."

jesus died on the cross so we could have eternal life

typical preachers spew out traditions of men, which make void the Word of God....sorry you never heard....

1 John 3:8

He that committeth sin is of the devil; for the devil sinneth from the beginning. For this purpose the Son of God was manifested, that he might destroy the works of the devil.

Because we have all sinned against a perfectly holy and righteous God, we all deserve eternal separation from God in hell (Rom. 6:23). However, God loves us so much that He sent His only Son Jesus to die on the cross as our Substitute so we don't have to go to hell. Christ died for our sins, was buried, and rose from the grave three days later (1 Cor. 15:3-4). He gives eternal life freely to anyone who simply believes in Him. No one can be saved by doing good works. Salvation is by grace alone through faith alone in Christ alone (Eph. 2:8-9).

"Verily, verily, I say unto you, He that believeth on me hath everlasting life" (John 6:47).