Count it all joy, my brothers  when you meet trials of various kinds, 3 for you know that the testing of your faith produces steadfastness. 4 And let steadfastness have its full effect, that you may be perfect and complete, lacking in nothing.

James 1:2-4 English Standard Version

The Apostle James tells us to count our trials as joy because the testing of our faith produces steadfastness. Steadfastness is a well-grounded faith that endures and even flourishes during times of pain and affliction. Instead of abandoning hope and sinking into fatal resignation, we each become a stronger person able to deal better with problems and disappointments. 

God uses trials to increase your capacity of faith to live life abundantly.

Whilst God is not the author of evil and suffering, He is sovereign over the circumstances in your life and that of the world. Though trials may potentially weaken your faith and even affect your confidence in God, learn to see trials as God's way of highlighting issues we never thought we had and His desire of working with us to heal and restore us. If it was not for trials, we would never be able to imagine we have a worry problem or an anger issue.

Going through a trial can act like a quality control measure. While they don't necessarily produce faith, trials reflect and reveal the kind of faith you have in God right now. It is not because God needs to know but because He wants you to know it for yourself. The good thing is, even if you have very little faith in God, He can and will increase it for you to endure and continue to thrive when the storms of life rises up against you.

If we do not believe God is lovingly good and gracious, then trials might lead us to become bitter and resentful towards God. This is what happened to the children of Israel in the Old Testament. They grumbled against God on many occasions and were never satisfied with God's generous provision and care for them. In doing so, they denied themselves from entering the Promised Land. If you give up and turn away from what God wants to heal and restore in every area of your life, it would be harder to face the future without that very faith that He wants to give you.

By persevering with a steadfast faith in hard and trying times, James encourages us that we experience maturity, wholeness and freedom. This capacity of faith brings us to a place of full persuasion that God is who He says He is and He will do what He said He will do.  In short, God will never fail us in every circumstance.