This is the testimony in essence: God gave us eternal life; the life is in his Son. So, whoever has the Son, has life; whoever rejects the Son, rejects life.
My purpose in writing is simply this: that you who believe in God’s Son will know beyond the shadow of a doubt that you have eternal life, the reality and not the illusion. And how bold and free we then become in his presence, freely asking according to his will, sure that he’s listening. And if we’re confident that he’s listening, we know that what we’ve asked for is as good as ours.