Dad installed a chinup bar in a doorway and used it everyday.  He challenged me to a contest when I was visiting.  I was amazed at his stamina but still beat him – hey, I was 30 years younger.  But now, at the age he was, there’s no way I could measure up to what he did then.  Unless I practiced.  The training regimen of olympic athletes is scary intense.  They punish themselves with every greater challenges til they know they can push through them.

In a similar way, we are encouraged to accept the various trials of life as opportunities to train our faith and develop our capacity to patiently push through.  

Count it all joy, my brothers, when you meet trials of various kinds, for you know that the testing of your faith produces steadfastness. And let steadfastness have its full effect, that you may be perfect and complete, lacking in nothing.  (James 1:2-4)

To test a diving board, you jump on it, tentatively at first but then with greater and greater force.  If you can’t break it then you know it will hold you.  You trust it  Same thing with faith; you jump on it to know if it will hold.  You test faith with trials.  As you learn your faith will hold, you become more able to endure life’s trials with steadfastness.  You become “perfect and complete,” in the sense that you are “good to go” in the faith department.  The faith is not in your own toughness but in Jesus’ ability to hold you safe, no matter what.  Like this:

For I am sure that neither death nor life, nor angels nor rulers, nor things present nor things to come, nor powers, nor height nor depth, nor anything else in all creation, will be able to separate us from the love of God in Christ Jesus our Lord.  (Romans 8:38-39)