If our Lord Jesus Christ did not rise from the dead in the body in which he died, then immortality in the New Testament sense of the word has never been brought to light.
But he did so rise.
He made that clear on the first Sunday night after his resurrection.
The disciples were gathered together in the room.
The supper table was spread.
No one cared to eat.
The story had been going all day that Jesus had risen.
The women said so. They persisted that they had seen and talked with him.
Two men claimed, also, to have seen him, walked, talked and broken bread with him, that very afternoon.
The disciples did not believe it.