Why did Jesus Die?

 Why did Jesus die 2000 years ago?
He did not have to die. Because he was God's eternal Son, he was immortal.

The first people were immortal before the Fall. God warned them not to eat the forbidden fruit. If they did, they would lose their immortality.

And the LORD God commanded the man, “You are free to eat from any tree in the garden;
but you must not eat from the tree of the knowledge of good and evil, for when you eat from it you will certainly die.” Gen 2:16–17 NIV

The first Adam was created without sin and was therefore immortal, but when he sinned he became corrupt and mortal. Since then we have all been born with a corrupt and mortal nature.

Jesus was born without our corrupt nature. Paul wrote that Jesus is the last Adam, the heavenly seed for a new humanity.

For since death came through a man, the resurrection of the dead comes also through a man.
For as in Adam all die, so in Christ all will be made alive. 1 Cor 15:21–22 NIV

Jesus willingly gave up his physical immortality to suffer the punishment for my sin and yours.

His last word on the cross was the voluntary sacrifice of his earthly life.

Then Jesus, crying with a loud voice, said, “Father, into your hands I commend my spirit.” Having said this, he breathed his last. Lk 23:46 NRSV

For God so loved the world that he gave his one and only Son, that whoever believes in him shall not perish but have eternal life. Jn 3:16 NIV