Hi John Michael,
The Bible speaks of two different kinds of death. Physical death and spiritual death. Matthew 10.28 addresses this. “Do not be afraid of those who kill the body but cannot kill the soul. Rather, be afraid of the One who can destroy both body and soul in hell.”
For the person who has trusted in Jesus as their personal Savior to forgive their sins and give them eternal life the Bible promises:
2 Corinthians 5.8 To be absent from the body is to be present with the Lord.
Isaiah 57.2 Those who walk uprightly (trust in Christ) enter into peace; they find rest as they lie in death.
1 Thessalonians 4.14 “…God will bring with Jesus those who have fallen asleep in Him.”
First Corinthians 15.12-17 is perhaps the more direct answer to the question, “Why is the resurrection of the dead important?”
“But if it is preached that Christ has been raised from the dead, how can some of you say that there is no resurrection of the dead? If there is no resurrection of the dead, then not even Christ has been raised. And if Christ has not been raised, our preaching is worthless, and so is your faith. In that case, we are exposed as false witnesses about God. For we have testified about God that He raised Christ from the dead, but He did not raise Him if in fact the dead are not raised. For if the dead are not raised, then not even Christ has been raised. And if Christ has not been raised, your faith is futile; you are still in your sins.”
So the purpose of our resurrection is to prove the supremacy and superiority of Christ and ultimately to point always to the One who “has the power to lay down His own life and to take it up again.” John 10.18.
The other purpose, as stated in your earlier post, is to give an account for the decision we have made regarding where we have chosen to spend our eternity and also how we lived the life He gave us. Like Job in the Old Testament, we will not be doing the questioning. God will. We will know that His judgements are based on full knowledge, justice, truth and love.
I hope this has been helpful and will help your friend as well. Please let me know if something I have posted is unclear and needs further elaboration.
Grace and peace,