John 17:3

John 17:3. And this is life eternal, that they might know thee, the only true God, and Jesus Christ, whom thou hast sent.

To know God, is eternal life. If you know God, if you know Jesus Christ whom he has sent, you are spiritually quickened. That knowledge has brought to you, nay, it is, in itself, the new life: "This is life eternal," - not life for a few years but life eternal. Mark the final perseverance of the saints, how they shall hold on and hold out for ever.