Religion is like handing flight instructions to a caterpillar.  It asks the impossible and so it's inevitably defeating and pointless.  The Gospel, on the other hand, transforms caterpillars into butterflies and calls them to take to the skies and "Fly!"  Peter tells us that Christians were saved for holiness.  And freedom.  And obedience.  And love.  And so when God calls us to be holy as he is holy, he's inviting us deeper into our destiny.  And after putting giant wings on our back and changing our nature, he now calls us to watch as he teaches how to fly.  That's what learning holiness is like.  It's not simply a command to the Christian; it's a privilege, an opportunity, a gracious blessing.