The Lord said that no greater gift can a man give than to lay down his life for a friend. This passage seemingly refers to physical life in context IMO (since we have the authority to actually give up our physical life for another)
And let me caveat this by saying that I see no where in Scripture where this is possible so this thread is purely hypothetical.
If the Lord made provision at some point in the future, would you exchange your place in Heaven with a lost loved one in hell FOR ETERNITY?
If the answer is no for just one loved one, how about for all your loved ones whom are lost either currently living or already dead?
Pondering on my own answer to these questions brings to mind passages in where Jesus declares earthly loved ones hardly matter when blocking you from eternal life: Matthew 12, Mark 3, Luke 14 off the top of my head.
Kinda makes me want to get busy, what do you think?