First of all, Jesus gives the perfect example of how we are to love one another.  Our love is to be completely unselfish to the point of giving one's life for one's friends.  Here Jesus distinguishes between friends who obey the commands of Christ freely and with full understanding and slaves who obey because they must.

Secondly, these lines point up divine election.  It is not we who have chosen God however self-motivated our choice might seem to us.  Rather all our efforts are in response to God taking the initiative in our lives.

Finally, Jesus never asks us to do anything he was not willing to do.  The loving obedience he asks of us was that offered by him to his Father.  His unselfish love on the cross is the ideal and source of inspiration for us.  Happily for us, the joy and enthusiasm of the early disciples as recorded in Acts can also be ours to the extent that we bear the fruit of this commandment of loving one another.