Ask yourself this question:
For what purpose did God make me? Why did He want me in the world?
This is quite certain. God put you in this world to carry out some work for Him. He made you for it. And He wants you to be a success and not a failure; He wants you to bring Him credit. As the Bible says, you were created for His glory. Have you brought God any glory by your life? Do people want to follow Christ because of you?
Now, does this seem impossible?
Have you a garden? And have you any fruit trees in it? If so, in the autumn you will expect fruit from them. A gardener once said to a lady who was walking round the garden of which he had charge:
"I always have success with my plants. I never keep anything that does not bring me credit. If plants don't flower as they ought, I pitch them away; if my apples won't bear, I root them up."
Ah! How good, and patient, and long-suffering is our Heavenly Father with His plants and fruit trees! What fruit are you bearing for Him? What sweet scented flowers are blossoming on your stalk? Have you been a failure or a success in His garden?
"His workmanship!"
Think of it when you are quarrelling and stamping with rage, when you're sulking, when you're telling untruths, and doing things in secret which you know you ought not to do.
God's workmanship! Did He make me for this? I am not bringing Him credit. I am bringing dishonour upon my Maker. I am like a watch that won't keep time, that is useless, that is no good to anyone.