"Not only that, but we rejoice in our sufferings, knowing that suffering produces endurance, and endurance produces character, and character produces hope, and hope does not put us to shame, because God's love has been poured into our hearts through the Holy Spirit who has been given to us."  (Romans 5:3-5)

There are several references to trials and suffering that begin with a call to rejoice.  I don't know about you but my first and gut reaction to suffering is not to rejoice.  Maybe that is why we are commanded to rejoice!  We can rejoice in suffering when we make the connection between suffering and growth.  Suffering is not the only way, but is not an unusual way and maybe even the normal way God produces growth in us.