Believing

 Everything that the Father gives me will come to me and I will not reject anyone who comes to me, because I came down from heaven not to do my own will but the will of the one who sent me.  And this is the will of the one who sent me, that I should not lose anything of what he gave me, but that I should raise it on the last day.

For this is the will of my Father,
that everyone who sees the Son and believes in him
may have eternal life,
and I shall raise him on the last day.”

John 6: 35-40

It comes down to this - that anyone who believes that Jesus is the Son of God will have eternal life.  He is not a just a great prophet or teacher; He is the One who will raise me up from the dead and through Him I can ascend to the Father in heaven.